The word photography comes from two Greek words, which mean “drawing by light”.
There is at present no field of human activity that is not directly or indirectly touched upon by photography.

Photographic process was not discovered overnight.
It took many years and a lot of effort from several scientists to discover the process. 

Let us have a historical insight. 

The early alchemists used to know about the effect of light on silver salts. At the beginning of the 19th century, Wedgewood, successfully reproduced images as negatives on paper impregnated with silver salts. A few years later, in 1819, Herschel discovered a unique property of thiosulphate, which we call is the fixing property. Thus he set the doors open for the first pictorial reproduction and in 1839 for the first exhibit, called photographs. The same year, Daguerre, a french scientist published his formula for manufacturing of the familiar daguerreotype.

A few more years later, Maddox discovered the gelatin dry plate.

Vogel, in 1873, found that the light sensitivity of silver halide crystals is greatly increased by the dye molecules adsorbed by them. Transparent roll film was introduced by George Eastman in 1889 and the famous Wratten panchromatic plates were introduced in 1906.

Now it is time we looked at the photographic process.

Silver halides are the most widely used sensitive substances in photographic processes. These light-sensitive silver salts are prepared in the dark as an aqueous gelatin emulsion. Certain dyes, various classes of sulfur and gold compounds, anti-fogging agents, hardening agents, stabilizers, coating aids, etc are added with the emulsion.

After some additional treatments, this emulsion is coated on film support of cellulose acetate, polyester, or glass. 

Exposure of the emulsion in a camera results in a photochemical reaction on the surface of the silver salt crystal. In silver halide crystals, internal dislocations act as electron traps. When some energy in the form of light is absorbed by the silver halide, a free atom of silver is liberated. This silver atom acts as a center which invites more photolytically generated silver atoms until a mono positive tetra silver ion is formed. Thus photolytic silver constitutes an image and forms effectively in proportion to the incident light of the color to which the crystal is sensitive. Thus an object is produced in the form of a dark image.

The result of this process described here is negative. The density of the image depends upon the number of crystals exposed. 

Positives are generally produced by first developing the negative silver image and then dissolving the silver image in an oxidizing solution or bleach. The residual complement of silver halide, which has the configuration of the positive image, is uniformly fogged either physically or chemically and then developed to give a positive silver image.

Silver halides of the emulsion supply the film with sufficient metallic silver when the developer is employed. As a result, we obtain a visible image from the negative.

Now let’s see how black and white materials are processed.

Modern developing solutions contain mainly four functional constituents. They are- an organic reducing agent, a preservative, an accelerator, and a restrainer.

The reducing agent chemically reduces the silver halide to metallic silver. Chemically, they are substances like polyhydroxide, amino hydroxide, polyamine derivatives, etc. 

Preservatives guard the developer against air oxidation.  The most common preservative used is sodium sulfite. 

Accelerators increase the alkalinity of the developing solution. Eventually, the activity of the reducing agent is increased. 

To maintain the speed of the developer, a restrainer, for example, potassium bromide or benzotriazole is employed.

The processing of black and white photographic materials is ended by a wash. After washing, the materials are dried with heat.

This is how we get what are called photographs. 

Now we will see how colored photographs are produced.

Color photography is based upon the principle that the colors of nature can be represented to human eyes and brains by mixtures of blue, green, and red light. Mixtures of these kinds have been produced by projecting colored beams of light in ‘register’. These beams of light emanate from properly prepared transparent positive images. They can also be produced by modulating or by silver images, microscopic blue, green, and red filters which are juxtaposed on support. In the method, the eye receives  the required amounts of green blue and red light to reproduce the intended color. An ideal electronic analog of this system is a color television picture tube. The use of green, blue and red beams or filters is difficult in practice and requires a lot of light energy. Alternatively, most methods of color photography are based on the use of the complements of blue, green, and red, which are yellow, magenta, and cyan respectively. Yellow results when blue is absent from white light. Similarly, magenta is absent when the green light is not present, and cyan, when the red light is absent. Thus à yellow filter can prevent the blue component of white light and permit only green and red; magenta prevents the green light from passing and allows only blue and red light to pass, and cyan controls red while permitting blue and green light to go through. Combinations of different proportions and densities of yellow and magenta produce a variety of colors, generally including orange and red. Similarly, yellow and cyan produce a variety of colors including green and magenta and cyan produce a group of colors including blue. There is a way these combinations can be affected.

The way is to superimpose layers of dyes on a single support.

Originally pigment layers were applied on one upon another and that is how color prints were prepared.
But, as there are much better dye-transfer systems available now, this process has almost become obsolete.

However, there is still some highlight on the pigment process as prints thus produced possess more permanent colors than those done with the help of dyes.

Dyes for color photography are produced according to the following set of reactions:

Exposed silver salt + developer → oxidized developer + silver

Oxidized developer + coupler → dye

This process requires that only one layer develop at a time and also that all reactants

be washed out of the photographic material before the next dye is produced. Preparation of each layer for development requires careful control. The coupler is introduced to the emulsion by the manufacturer. Then the exposed silver salts can comfortably be developed in all layers.

The oxidized developer reacts with the coupler immediately and thus a proper dye is formed.

Two types of color photographic processes are available. They are- negative and reversal. Negative processing is the one where an incorporated coupler is used.

It results in color

development in the very region of the exposed silver salts. In the regions that are exposed to blue, a yellow dye is formed. Similarly, a magenta dye is formed in regions exposed to green and a cyan dye is formed in regions exposed to red. The negative can be used to produce a positive. In making the print, the dyes in the negative are responsible for controlling the amounts of blue, green, and red light reaching the layers of emulsion on the print material.

The emulsions also contain incorporated couplers.

The reversal process involves the development of exposed silver salts to a silver negative.
The remaining silver salts are not exposed universally but selectively and color developed to yield dye layer by layer.

New processes of color photography are being developed. We hope that what is done in a somewhat difficult way nowadays can be done with much ease tomorrow.

We are awaiting that tomorrow eagerly. 

The post Photographic Chemistry : The Process of Producing Photographs appeared first on Chemniverse.

Since the very beginning of civilization, men have had an irrepressible curiosity about planets in the solar system. They have always wondered about what these planets look like. We don’t know how many people have drawn imaginary pictures of these planets in the canvas of their eyes, but we can surely guess that the number is huge. With the passage of time, science has paved the way for the termination of almost all sorts of mystery and imagination.

And chemistry has always been there with the explanation! Let’s have a look at how chemistry explains why planets possess different colors!

Thanks to the technological development and advancement of science in the last hundred years, our perception about the planets in our solar system has improved a lot. We have been able to identify which color a planet possesses and at the same time we can also understand why it does so.

What is more satisfactory is we can identify the colors not only of the planets which are close to the sun but also of the ones that are located far away from the sun.

Which color a planet appears as mainly depends on two factors.

The chemical substances its surface is made of
Absorption and reflection of sunlight by the surface or the atmosphere

Planets of the solar system infographic illustration

Earth

If you look at earth from space, you can see beautiful blue oceans, green land and brown soil. But as you all know, the earth’s surface is predominated by water. To be specific, almost 71% of the surface is occupied by water and the other 29% is made up of lands. Now, water absorbs the radiation from the sun. We know that the radiation of light that the sun emits is white in color. White is a combination of seven colors (violet, indigo, blue, green, yellow, orange, and red). Now the water on earth’s surface absorbs six out of these seven colors and reflects only blue. That is why earth appears as blue when looked at from space.

If you wonder how this is related to chemistry, you better know water is a chemical substance, and had the surface been covered mostly with some other chemical compounds other than water, the earth would not have looked blue!

Mercury

Mercury’s surface is believed to contain a lot of dust and is rocky in nature. The dust is so much in quantity that the surface is actually covered with a layer of dust. As you all know, dust is composed of a lot of silicates, leading the surface to appear brownish-grey in color.

One interesting thing about mercury’s surface is that it is very similar to that of the moon.

Venus

Venus is in fact the largest of the earth’s nearby planets. Its surface is also rocky and grey in color. But when you look at venus from space, you may observe yellowish-white clouds. The color of the clouds is due to the presence of sulphuric acid. Again the presence of sulphuric acid comes into being because venus possesses a very dense atmosphere. There is also a lot of carbon dioxide in its atmosphere.

Therefore we can come to a conclusion that it is the combination of contribution from the carbon dioxide in the atmosphere and the sulphuric acid in the clouds which is responsible for venus to appear as yellowish-white.

Mars

The surface of Mars contains a high concentration of iron oxide. In other words, we can say that the surface of Mars is covered by dust particles, which contain a lot of iron oxide. This is what is responsible for the reddish-orange appearance of Mars.

The reddish-orange glow of its surface can be distinguished from the earth, making it the worthiest candidate of the name it is called by, the Red Planet.

Jupiter

Jupiter is the largest planet in the solar system. Its atmosphere is mainly made up of two of the lightest gases – hydrogen and helium. That is why, this planet is considered as a gas giant. The entire planet is surrounded by a large band of clouds of different colors (eg, red, brown, yellow, orange, and white). Again this large band forms due to the presence of elements like ice crystals, ammonia crystals, water droplets, and the like.

It should not be out of place to mention that Jupiter has a red spot that can be observed from the earth with the help of a telescope.

Saturn

Like Jupiter, Saturn is also considered as a gas giant. Its atmosphere is made up of hydrogen-helium, a trace amount of hydrocarbons, steam, ammonia, and phosphine. All these chemical substances contribute to its having a yellowish-brown appearance. You must have heard of Saturn’s rings. These rings are made up of ice crystals and are of the same appearance as the planet itself.

However, colors of these rings can vary with concentration and in case other materials are present unusually.

Uranus

Uranus has a greenish-blue appearance. It is due to the presence of methane gas in the atmosphere. However, the atmosphere is mainly made up of hydrogen and helium. Uranus is the coldest of all the planets as it has an icy layer of clouds around it.

It might surprise you that the temperature of the cloud can get even below -200° celcius.

Neptune

Neptune’s atmosphere is also made up of hydrogen and helium. But much like Uranus, Neptune also possesses methane gas in its atmosphere. Neptune therefore also appears as blue.

Methane gas in the atmosphere absorbs red light and reflects only blue.

Without chemistry, reasons behind planets’ having different colors cannot be explained,
for you all can see – chemistry here, chemistry there- chemistry everywhere!

The post What are the colors of planets in solar system: Explained With Chemistry appeared first on Chemniverse.

Why? Because alcohols can be converted to almost every other aliphatic compounds!

What does the general formula look like?

Alcohols have the general formula ROH, where R is an alkyl or substituted alkyl group.

Let me explain this in an easier way.

We can say that when a hydrogen atom of an alkane is replaced by a -OH group, we get alcohol. Now after you take away one hydrogen atom from an alkane,  make a hydroxyl group take that empty position, dare you still call it by the same name? No, you have to get it a new name, the format of the name being (alka+nol).

This is how we get what are called the common names of alcohols.

For example, if you replace a hydrogen atom of propane by a -OH group, the alcohol you get would love to be called by the name propanol. Sounds sweet, doesn’t it?

Classification based on the position of the carbon bearing the -OH group

Now just like your schooling is divided into different stages such as primary, secondary and higher levels, alcohol, according to the kind of carbon that bears the hydroxyl group, is classified into three types – 1° or primary,  2° or secondary and 3° or tertiary.
Well, as you can see, all degrees certainly do not always represent temperatures.

The alcohol where the carbon atom adjacent to the hydroxyl group is bonded with only one other carbon atom is called 1° or primary alcohol. Similarly, the one where the carbon atom adjacent to the hydroxyl group is bonded with two other carbon atoms is 2° or secondary alcohol.

Now you should be able to define the 3° or tertiary carbon atom. Let me leave this task for you, please.

Propan-1-ol, propan-2-ol and 2-methylpropan-2-ol are examples of the three above kinds of respective systems. These are named according to the IUPAC system, one of the most versatile and the smartest systems ever introduced in the field of science.

For the simpler alcohols, the common names are used often. See! We human beings are not the only ones who have got gorgeous names, alcohols have got some too!

Classification based on structure: 

On the basis of the structure, alcohols are divided into two kinds- aliphatic alcohols and aromatic alcohols.
Again, Aliphatic alcohols may be saturated and unsaturated according to the nature of C-C bond.

Classification based on the number of hydroxyl groups present:

(a) Monohydroxy alcohol: One -OH group present.

(b) Dihydroxy alcohol : Two -OH groups present.

Ethylene glycol is a good example of dihydroxy alcohols.

1. c) Trihydroxy alcohol: Three -0H groups present. Glycerine is probably the most familiar example of this kind.

1. d) Polyhydroxy alcohol: Four -OH groups present. Sorbitol is a familiar example of polyhydroxy alcohols.

Physical Properties Of Alcohols

In alcohols, the carbon and the oxygen atoms are in sp3 hybridized state.
Out of the four hybrid orbitals of oxygen atom, two sp3 orbitals are completely filled.
These two completely filled sp3 orbitals do not take part in the bond formation.
The other two half-filled sp3 orbitals of oxygen atom take part in the sigma bond formation.
Thus C-O bond in alcohol is formed by the overlapping of one half-filled sp3 orbital of oxygen and one sp3 orbital of carbon atom of the alkyl group.
The bond between carbon atom of alkyl group and oxygen atom is thus sp3-sp3 sigma bond.
The other half filled sp3 orbital of oxygen forms a bond with orbital of hydrogen atom.
Thus O-H bond angle in alcohol is sp3

-s sigma bond. The C-O-H bond angle in alcohol is 105° which is less than the normal tetrahedral angle (109°28′).

This is because of the fact that the two unshared and completely filled sp3 orbitals of oxygen atom repel each other causing the reduction of C-O-H bond angle (VSEPR theory).

Common alcohols are liquids at room temperature. This must be a fact of no wonder to you as you have already watched a lot of movies where villains drink a lot of alcohol from glasses and you know what is drunk from glasses cannot but be liquids.

However, highly branched alcohols i.e. those with more than twelve carbon atoms are solid at room temperature.

Alcohols are colorless too. Oh! What a relief for those who are color blind!

Most of the common alcohols have got a fruit-like smell, making their presence quite easily detectable.

Let us look at the boiling points. Among hydrocarbons, the factors that are responsible for the determination of boiling points are mainly molecular weight and shape. Alcohols, as expected, show increase in boiling points with increasing carbon numbers and decrease in boiling points with branching. But what is unusual about alcohols is they boil so high, much higher than hydrocarbons with nearly similar molecular weights (Aristocracy, isn’t it?).

It is due to the greater energy required to break the hydrogen bonds that hold the molecules together.

The O-H bond in alcohols is highly polar which arises due to the high electronegativity difference between oxygen atom (3.5) and hydrogen atom (2.1). As a result, the oxygen atom of -OH group in alcohol carries a partial negative charge. Thus the polarity of -OH bond in alcohols gives rise to forces of attraction between partially negatively charged oxygen atom of one alcohol molecule and the partially positively charged hydrogen atom in another alcohol molecule. The force of attraction thus produced between hydrogen atom and another electronegative atom two molecules is known as hydrogen bond. Thus numerous hydrogen bonds are produced among the alcohol molecules. The alcohol molecules get associated with hydrogen bonding. Consequently, much higher energy is required to break these numerous H-bonding to bring the associated molecules in monomeric forms. As a result, the b.p. of alcohol becomes high. On the other hand, alkanes have no (-OH) group. So hydrogen bonds are not formed between the alkane molecules.

As a result, the b.p. of alkanes are low.

The fact that the lower alcohols are miscible with water also reflects their ability to form hydrogen bonds with water. The higher alcohols have bigger insoluble alkyl groups of comparatively higher mass. So the hydroxyl (-OH) group can not form hydrogen bonding with water molecules pulling the bigger alkyl group.

Therefore, alcohols of higher mass do not dissolve in water.

We better be like alcohols and with our close ones form a bond too strong to be broken easily!

The post Alcohols and their physical properties: A Proper Guideline appeared first on Chemniverse.

Acids have always been a substance of fear, something we try to stay away from. While there are harmless weak acids, there are also very strong acids that are harmful to even touch. But there is another type of acid we don’t hear about much. Even inside a chemistry lab, they are subjects of extreme caution. They are the mysterious superacids. And they are so strong that people question their existence. Today we will try to discuss this idea of superacid and a few of its members.

What is Acid?

You probably already know what an acid is. In a normal sense, acids are sour and astringent substances. A very common example would be lemon juice which contains citric acids or the must-have vinegar which is just watered-down acetic acid. Very familiar right?

In chemistry, an acid is a molecule or ion that can accept electron pairs or donate protons (hydrogen ion, H+). For example, acetic acid donates a proton to baking soda (NaHCO3) in the following manner

CH3COOH + NaHCO3 = CH3COONa + CO2 + H2O

You can see that an H+ was donated and Na+ took its position. By the way, this is a fun little experiment that you can try out at your home. It produces a lot of CO2 which comes out in the form of bubbles. The reaction is vigorous but safe. Be sure to use them in small amounts or someone is going to get scolded (or beaten) by their mm.

Strength of Acid or Acidity

The examples given earlier do not sound so scary. So, what about the warnings we hear so much? The warnings are indeed correct. Acids can be divided into two types: 

1. Weak organic acids e.g., ethanoic acid (vinegar)
   2. Strong mineral acids such as hydrochloric acid (HCl), nitric acid (HNO3), etc.

While superacid is an acid that is stronger than even pure sulfuric acid. We will come to it later. Superacid is best served cold.

Let’s talk about the strength of acids first. As said earlier, organic acids are weaker while mineral acids are strong. But what is this strength based on and how can you measure it? 

The strength of an acid solution is often expressed in terms of the number of hydronium ions (H3O+) it can generate in a water solution. 

HCl + H2O = H3O+ + Cl–

The amount of H3O+ is measured in the concentration unit molL-1 or shorter “M” (pronounced as molar). The more the concentration of H3O+, the stronger is the acid.

The pH Scale

But there is a better way of comparing the strength. That is by calculating the negative logarithmic value of concentration.

This value is called pH value and was introduced by Danish chemist Søren Sørensen in 1909.

So, pH= -log[H3O+]; here [H3O+] = concentration of hydronium ion

The negative sign means that the pH and strength are opposite to each other. The stronger the acid the lower the value of the pH is. And for each unit of pH that decreases, the strength of the acid increases by 10 times!!

That is not all. The pH can have a value ranging from 0 to 14 which is called the pH scale. The pH value 7 means a neutral solution. As the value increases the solution becomes more alkaline. And you already know that as the pH decreases the solution becomes more acidic.

But as a matter of fact, all acids that have a pH value between 0 and 7 are considered weak inside a chemistry lab. Wait a moment. Stomach acid contains HCl and it has a pH between 1 and 2. So, shouldn’t it be a weak acid? No, HCl is a strong acid but it can have a dilute solution. You can make solutions of varying concentrations. 

If you make a 1 M solution of HCl it produces the same amount of H3O+ ions and the pH will be 0. The pH of 1 M acetic acid should also be 0 then, right? Bzzzzzz. Wrong answer. The pH value of 1 M acetic acid is 2.38 meaning it is about 240 times weaker than the 1 M HCl solution!! This is because acetic acid is a weak acid and doesn’t produce as many H3O+ ions and thus weaker. What does it produce less? That’s another big explanation. Let’s forget that question for now.

Strong acids vs. The pH Scale

A question should be popping up in your mind by now, “How much concentrated acid solutions can we make?” You will be surprised to know that it is possible to make a 38% HCl solution that has a concentration of almost 12 M!! For sulfuric acid that would be 18.4 M!! Any more than that is out of water capacity. And that’s what you call strong.

We are almost in the zone of superacid, just a bit more.

So, what would be the pH of 12 M HCl? It should be -12. Although it is mathematically correct, it is not chemically possible. Few reasons being

• At high concentrations, even strong acids do not dissociate fully in water and produce a lower number of H3O+ ions.
• The amount of water per acid unit simply becomes inefficient.
• Moreover, the pH meters don’t work at high acidity due to “acid error”.
• One more important fact is that the acid species being produced changes which greatly changes the activity coefficient of the ions.

These are but a few reasons. Also, a lot of chemistry goes into explaining them.

 There is yet another problem that is the “leveling effect”. You have to go back a bit to understand this. The pH of 1 M HCl is 0. And it is the same for 1 M HNO3 because it too is a strong acid. The same goes for other strong acids too. Did you see what just happened? All of them got leveled to the same strength. This is because whatever acid you put into water; the water turns it into an H3O+ ion. How envious is he!! As water is the solvent, it is his rule.

Because of all these reasons, pH is used only in measuring weak acid solutions.

As a result, when comparing superacids, we cannot use pH or anything that involves mixing acids into water.

The Hammett acidity function

So, what do we do now? This was answered by physical organic chemist Louis Plack Hammett.

He proposed the use of an acidity function that omits the water part from the pH equation and can be used for concentrated solutions of strong acids. The acidity function is called the Hammett acidity function and is denoted by H0.

The Hammett acidity function, 

H0 = pKBH+ + log BBH+

H0 is analogous to pH and it is as if the pH scale has been extended to the negative direction.

Moreover, the value of H0 is equivalent to pH assuming the acid dissociated normally in water. But that is not the case.  So, remember that H0= -12 does not mean that the pH is also -12.

Superacid

After listening to all those things, we can finally talk about the superacid. It’s obvious from the name that superacids are acids that are so strong that they cannot only be called strong acids anymore.

So how strong will an acid have to be before you can call it a superacid? Well, pure sulfuric acid is the strongest acid that you can find in nature. As said earlier, it has an of -12. 

Any acid that is stronger than 100% pure sulfuric acid i.e., that has an H0 value lower than -12 is called a superacid. Superacids are generally a medium where the chemical potential of a proton is higher than in pure sulfuric acid.

There are a lot of compounds that do not react with even sulfuric acid but very few compounds can ignore superacids.

The idea of superacid was known from as early as 1927. But it became popular when George A. Olah first prepared a superacid called the magic acid, a 1:1 mixture of fluorosulfuric acid (HSO3F) and antimony pentafluoride (SbF5). He was working with hydrocarbons and found that a superacid can produce carbonium ion or carbocation, an ion with a positively charged carbon in it. Carbonium ions are very important in polymer making. He won the Nobel prize in 1994 for his works in carbocations.

If you are wondering about the name, magic acid, it came up when coined after chemists placed a paraffin candle in a sample of magic acid after a Christmas party. The candle was dissolved almost instantly, showing the ability of the acid to attack hydrocarbons. Please, don’t even think of using a superacid for a magic trick, you know why.

Let’s look at a few examples of superacids and how dangerous they are. After all, that is what we all are after, right? Haha. So, without further ado, let’s start.

Triflic Acid

Triflic acid is a superacid with an H0 value of -14.9. This means that it is 1 a thousand times stronger than pure sulfuric acid. The full name of triflic acid is trifluoromethanesulfonic acid and it has the chemical formula CF3SO3H.

It has strong protonating power and is used as a catalyst in many organic reactions where hydrochloric acid or sulfuric acid are only moderately strong and won’t serve the purpose.

If it touches the skin it will give immediate burn to the skin and even damage tissues underneath. On inhalation, it causes fatal spasms. 

Magic Acid

As mentioned earlier, magic acid is a 1:1 mixture of fluorosulfuric acid (HSO3F) and antimony pentafluoride (SbF5). It is prepared by mixing hydrofluoric acid (HF), sulfur trioxide (SO3) antimony pentafluoride (SbF5). It has an H0 value starting from -19.2 up to 23 depending on the ratio of mixture components. Meaning it is 100 million times stronger than triflic acid and 100 billion times stronger than pure sulfuric acid!!

When comes in contact, it will cause serious injury if not death. It is so reactive that is kept under nitrogen which creates an inert surrounding.

It is used to produce higher-quality gasoline from crude fuels. The carbocation produces forms more complex bonds between them resulting in higher grade fuel.

SbF5 + HSO3F + CH4 = F5Sb − OSO2F−+CH+5

Still, it is not the strongest acid on earth. That position goes to Fluoroantimonic acid.

Fluoroantimonic Acid- World’s Strongest Acid

This is the strongest and most reactive acid known to man to this day. It is prepared by combining hydrogen fluoride (HF) with antimony pentafluoride (SbF5). The resulting acid is a monster with an H0 value of -28. That’s 10,000 times stronger than even the magic acid!! And 10 quadrillion times or 10 million billion times stronger than pure sulfuric acid!!!

It will not just burn you or not just kill you. It will eat through skin flesh bones everything. No matter what container you put it in, it will dissolve that and keep marching ahead except Teflon.

Yes, it only bows before Teflon. And used to produce the container for Fluoroantimonic acid. The very material used to make your frying pan. No need to thank me for giving you this good news. 

So why Teflon? Let’s look at the acid first. You will notice that almost all superacids contain the element fluorine. When fluorine-containing acids are mixed, the fluorine gets attached to multiple hydrogen ions. And it will give up the hydrogen ions readily for just about anything.

But Teflon is a polymer of tetrafluoroethylene molecules that already contains strong carbon-fluorine bonds and will not lose to even the strongest of acids.

That’s it for today. If you ever come across any super acid, it is probably best to stay away from it.

For now, we have frying pans, sorry, Teflon. If humans will ever produce an acid that can’t be stopped by anything is not a certainty. What certain is that we should always focus on what’s good for humanity, not just superacids but everything around us.

If you like the content, visit Chemniverse.com for more like this.

Have a nice day!!

The post Superacid: The Strongest Acids in the World appeared first on Chemniverse.

Let’s dig into the top 10 drug discoveries of all time.

10. Ether

Crawford Williamson Long is known to use ether as an anesthetic drug in surgery for the first time in history. Before that, nobody had believed it was a powerful drug for human beings. Diethyl ether has replaced the use of chloroform as a general anesthetic drug in the human body. It has a reviving property that helps the nervous system. It can be used safely to the shocked patient to get rid of hypertension and tachycardia. But the discovery of newer drugs has lessened the use of ether as an anesthetic drug rather than ether has been mixed with alcohol or chloroform to work as an anesthetic drug.

Though over the past few decades, new anesthetic drugs are evolving, the immense importance of ether can’t be overlooked at all. 

 09. Mechlorethamine

Mechlorethamine is commonly known as nitrogen mustard which brand name is Mustargen. If any of you are familiar with prostate cancer, then you will surely find this drug. It’s a revolutionary drug that has been used for over past decades only in warfare. But due to the development of the drug, it has been used as an anticancer chemotherapeutic drug. The function of this drug is to bind the DNA, crosslink two strands, and prevent duplication of cells.

Many diseases like Hodgkin’s disease, lymphosarcoma, chronic myelocytic leukemia are diagnosed with this drug as it has the efficacy in fungicides type cutaneous T cell lymphoma.

08. HIV Protease inhibitors

HIV is a virus that attacks the human body system which results in AIDS. The rate of getting infected with HIV is getting higher day by day. But the treatment of HIV is improving day by day. The drug that has changed the overall improving outlook of HIV is HIV protease inhibitors which have led to extraordinary success in the drug development arena. HIV always tries to copy itself as many times as it can. If anything can stop the HIV from multiplying then it can’t spread into the body. That significant role is being played by protease inhibitors. HIV injects its genetic materials into immune cells which results in a virus factory. Protease is an enzyme that helps HIV to replicate and a protease inhibitor stops the action of protease enzyme.

This is how HIV can’t copy itself.

07. Chlorpromazine

Suffering from anxiety and depression is a common ailment of today’s world. But before 1950 people used to take lithium to refrain from anxiety and depression. Chlorpromazine, commonly known as Thorazine has created a revolutionary change in the history of psychiatric medicine. Chlorpromazine is considered a low potency antipsychotic drug that has lower side effects. Research shows that it is 13% more effective than Latuda and Fanapt. For porphyria and tetanus treatment, this drug is also used. AIDS patients with delirium symptoms are also treated with this drug.

Though it has some adverse effects like sedation and parkinsonism, it has created an immense effect to treat bipolar disorder or mental ailment patients.

06. Morphine

German scientist Friedrich Serturner had first isolated the drug morphine in 1804. Merck started to marketize commercially in 1827. Morphine was widely used after the invention of the hypodermic syringe. The raw material of morphine is derived from poppy straw. It had a significant impact on the battlefield as it was used to get relief from chronic and acute pain. Morphine is effectively used in reducing the symptoms of shortness of breath for cancer and non-cancer patients. It is widely used for myocardial infarction and labor pain. It is also used for opiate substitution therapy ( OST ). It has some adverse effects that may imply some contradiction such as hormone imbalance, constipation, addiction.

Despite having a lot of adverse effects, it has opened a new methodology of the pain management drugs and drug development arena.

05. Insulin

There are about 422 million diabetic patients and 1.6 million deaths are caused by diabetes. There are two types of diabetes such as type 1 diabetes and type 2 diabetes. In type 1 diabetes, insulin can’t be secreted into the blood. In type 2 diabetes, beta-cell destruction is less frequent and it is pronounced much for the increased glucagon secretion. Insulin is a protein hormone that is produced by beta cells and pancreatic islets. Frederick Banting and Charles Herbert Best are considered to be the discoverer of insulin in 1921. Insulin is a hormone that is attributed to the conversion of sugar into energy. It increases the path of DNA replication and modifies the activity of numerous enzymes. Insulin can’t be taken by mouth rather it should be taken as subcutaneous injections by single-use syringe.

As the number of diabetic patients is increasing day by day, the intake of insulin is bearing more importance than ever.

04. Serelaxin 

Serelaxin is widely used for the treatment of acute heart failure. Serelaxin is a reorganized form of a hormone called relaxin that is generated during pregnancy. It also helps in reducing the increased blood output of the heart and blood flow in the kidney. It increases the calcium sensitivity of cardiac myofilaments and the phosphorylation of myofilaments.

According to Novartis, a safe and efficacy trial that is undergone by the FDA has declared that serelaxin has the ability to reduce the death rate by 37% compared to the patient who took standard therapy.

But it’s a matter of regret that this study went in vain as it didn’t meet the primary endpoint of the reduced cardiovascular death rate. Though it didn’t become successful, Novartis is committed to improving the lives of cardiovascular patients and for this, this study helps them a lot to improve in the drug development arena.

03. Contraceptive Pill

Austrian Scientist Ludwig Haberlandt first introduced hormones can be a way of contraception. The first approval of the contraceptive pill happened in 1960 by the FDA. Since then, the rate of taking contraception pills is getting higher and higher. But before 1960, it was a taboo to the people. Many women now believe that contraceptive pills have paved the way for women to become self-independent and create an impact on economic growth. It is estimated that 17.5 percent of women in the world are taking contraceptive pills. Though it is generally accepted safe to take this drug, it has some common side effects like breakthrough bleeding and amenorrhea.

It can create some impact on environmental aspects as several studies have shown that reducing human population growth can be an effective hack to climate change mitigation.

02. Aspirin 

In ancient Egypt, medicines were made from willow and salicylate rich plants. Hippocrates cited salicylic tea as a pain-relieving medicine. You probably are thinking why these examples are shown in this para. Here comes the answer. Over the past few centuries, salicylic acid is used to treat pain and the modification of that use is today’s aspirin. Aspirin’s popularity grew in the 20th century but it lost its pride after the development of paracetamol in 1956. It’s a prominent medication that is widely used for reducing pain, fever, and inflammation. In some cases, lower doses of aspirin can prevent death from a heart attack. It also has some properties to treat cancer, stroke patients, and even veterinary treatment. Like every other drug, it also has some demerits, it only should take under the proper instructions of a doctor.

But whatever it is, it has created an immense impact in the drug development arena.

01. Penicillin

In 1928, the advancements of antibiotics were laid because of the discovery of penicillin by Alexander Fleming. Statistics show that the antibiotic has saved over 80 million lives. Antibiotics are widely used for treating pneumonia, scarlet fever, and throat infections. Penicillin is a bunch of antibiotics that are derived from Penicillium molds. For this outstanding discovery, Alexander Fleming was awarded the Nobel prize in 1945. Many derivatives like procaine benzylpenicillin (procaine penicillin), benzathine benzylpenicillin (benzathine penicillin), and phenoxymethylpenicillin (penicillin V) are also considered as “penicillins”.

After the discovery of penicillin, the advancements of antibiotics got a new dimension of drug development that has enabled to save a million lives.

Final Thoughts

These are the top drug discoveries that we have found to describe. There may be a lot of varieties of drugs emerging day by day that is helping us to live a healthy life. Would you like to mention some drugs? What about your thoughts regarding this list?

Let us know that fact!

The post Top 10 Drug Discoveries of All Time appeared first on Chemniverse.

Jackfruit (Artocarpus heterophyllus Lam.) is a very popular and well-known fruit in Southeast Asia. Jackfruit is so popular in Bangladesh that is, in fact, is the national fruit of the country. 

Hello everyone, this is Chemniverse. 

Today we will talk about jackfruit nutrition and see how the chemical composition of the fruit is related to the nutrition facts. 

Jackfruit bears high nutrition value. It contains a lot of nutrients which gives its nutrition profile a very healthy look.

Jackfruit is a source of a moderate amount of calories. The majority of the calories are supplied by carbohydrates. 100 grams of edible jackfruit contain 30 to 35 grams of carbohydrates. One of the jackfruit’s most important properties is its protein profile. 100 grams of Jackfruit contain protein almost three to ten times as much as that contained by the same amount of apples, mangoes, and the like. So a mentionable portion of calories is also supplied by proteins. It should not be out of place to mention that fats present in jackfruit also provide some of the calories.

It has been found that, for every 100 grams of edible Jackfruit, we get around 93-95 calories.

Jackfruit is a fantastic source of potassium. Studies show that around 300 mg potassium in every 100 grams of jackfruit.
Foods rich in potassium have always been helpful for humans as they can play a vital role in controlling blood pressure. 

Jackfruit contains a lot of fibers as well. To be specific, 100 grams of jackfruit provide around 2 grams of fibers in general. Because of containing a very good amount of fibers, it has got a very low glycemic index. Glycemic index is what tells you how rapidly your blood sugar increases after taking a meal. As jackfruits have got a very low glycemic index, it helps blood sugar management.

Also, the fiber present in jackfruit helps digestion and reduces the risk for heart diseases.

Another very important thing about jackfruit nutrition is it has many powerful and effective antioxidants.
Antioxidants prevent diseases caused by free radicals and oxidative processes and reduce risks for many chronic diseases.

Vitamin C is a very important type of antioxidant present in jackfruit. 10-12 mg of vitamin C is present in every 100 grams of sliced jackfruit. Vitamin C is perhaps the most important vitamin for developing a good immune system. But there is no such mechanism inside our body that can produce vitamin C. So we have to eat foods containing vitamin C. And living these days, the covid-19 era, you cannot but know how important the role of vitamin C is against viral infections! But vitamin C has got other surprising benefits too.

For example, it is also very effective against skin diseases. Jackfruit also contains vitamin A, which also prevents many diseases.

Another important type of vitamin contained by Jackfruit is vitamin B3, also known as niacin.
Our body needs niacin for the metabolism process. 100 grams of jackfruits can supply up to one-fourth of our daily needs of niacin.

Jackfruit also contains a lot of carotenoids.
Some of the carotenoids are α-carotene, β-carotene, neoxanthin, luteoxanthin, zeinoxanthin, lutein, β-cryptoxanthin, etc.
These carotenoids are effective against diseases like cancer, cardiovascular diseases, etc.

If you look at jackfruit’s nutrition profile you would also find some phenolic contents, which are believed to prevent heart diseases.

Many phytonutrients are also provided by jackfruits. Among them, isoflavones, saponins, and lignans are the most important ones.
These nutrients fight against cancer, ulcer, and hypertension. 

Jackfruit is a great source of almost all kinds of minerals. We mentioned potassium before.

But calcium, iron, magnesium, sodium, zinc, copper, etc are also present in a good amount in jackfruit. 

Though we talked only about the chemical composition and nutrition facts of jackfruits, we cannot forget how tasty it is and how unique its flavor is!
Oh! What a blessing Jackfruit has been for us!

The post Jackfruit Nutrition Facts: It’s Health Benefits appeared first on Chemniverse.

If you were searching for methods to get rid of the moles that are ruining your garden, then unfortunately this is the wrong place. Nor is it the mole that you may see on someone’s chin. But the mole we will be talking about is also very important and infests throughout chemistry. It is the international unit for the amount of substance. And if you came exactly for this mole, then “Welcome”.

Which came before? The mole or Avogadro’s constant? This is a question harder than “Which came first, the egg or the chicken?” Let’s look a bit at the history. Oh, if you are still wondering about the egg and the chicken, the answer is “The egg”.

Origin of Avogadro’s Law and The Mole

The Avogadro’s constant and the mole have an intertwined history.  

In the year 1803, English chemist John Dalton revitalized the idea of Democritus that every substance is made up of tiny atoms. And this got Amedeo Avogadro, an Italian scientist, thinking about the relation between the amount of substance and the number of atoms.

He observed many things, like the electrolysis of water produced hydrogen gas and oxygen gas in a 2:1 volume ratio. From his observations, in the year 1811, he proposed that an equal volume of gasses contains an equal number of atoms or molecules under the same condition regardless of the nature of the gas. Which is known as Avogadro’s law or hypothesis. But he could not calculate the number of molecules in an amount of gas yet.

Not much was done about this number of atoms or molecules after that for a while. But the concept of the mole was developing. Because, by that time, the term relative mass was already familiar to scientists and they calculated in terms of mass. Relative mass is in the end, the ratio of masses of atoms that has no unit. So, even if you expressed these relative masses in other units their ratio would hold. 

And this relative mass expressed in gram was called a mole of that substance. It is not as complex as it sounds. Let’s look at an example. The relative mass of the carbon atom is 12. So 12g carbon means 1mole carbon. Similarly, 

1 mole of hydrogen= 1g hydrogen

1 mole of aluminum= 27g aluminum

I know what you’re thinking: “How did it get the name mole?” German chemist Ostwald coined the unit Mol from the word Molekül in the year 1894. Mole is the translated form of mol.

Note that the number of atoms in a mole is the same for every element, the same as Avogadro’s law.  But the value of this number could not be obtained for a long time. No, its approximate value was actually determined by Joseph Loschmidt in 1865 albeit indirectly and the term, Avogadro’s constant, was still not there. And so, people were still unaware of this discovery.

This term was first introduced by Jean Perrin in 1909 who defined it as the number of molecules in 32 grams of oxygen as it was the standard of the relative mass at that time. But as said earlier, they had yet to know the value. 

Perrin finally had a breakthrough when Robert Millikan determined the charge of an electron through his oil-drop experiment. And the value of the total charge of 1mole of electrons, the Faraday constant, was already known to scientists since 1834. Although you read a bit earlier that the term mole was introduced in 1894, there was already a term known as the equivalent mass which is similar to the mole but depends on valency. For electrons the mole and the equivalent mass have the same value and so is the total charge.

You might now wonder how did the scientists manage to determine the total charge of a mole of electrons without knowing their number. The answer is electrolysis. Faraday is the pioneer in this case. He determined the Faraday constant by measuring the amount of electricity needed to obtain one mole of mono-valent metal through electrolysis.

The value of Faraday constant= 96485 C = Total charge of one mole of electrons.

Charge of an electron= 1.602×10−19 C

So, Avogadro’s constant NA= 96485 C1.602×10-19 C = 6.022×1023

Jean Perrin later calculated the value of Avogadro’s constant in many different ways and was awarded the nobel prize for his work in 1926.

Knowing the past helps us learn new things from the people that came before us. We can learn both from their success and failure. Although you will not need history to do calculations involving moles or Avogadro’s constant, this story teaches us how the things we need might be in front of us and be never noticed.

This should be enough about history. Let’s look at the exact information you need to know.

Avogadro’s Constant or Avogadro’s Number

You have seen that the Avogadro’s constant is defined as the number of atoms in 16g of oxygen or the number of molecules in 32g of oxygen. We have to clarify because oxygen is found as O2 in nature which contains 2 atoms per molecule.

But this definition changed over time. Carbon-12 isotope replaced oxygen as the new standard. And so, the definition changed to- the number of atoms in 12.00g of carbon-12.

The definition changed yet again and in the year 2017, the BIPM (Bureau International des Poids et Mesures) defined Avogadro’s constant as the exact value of 6.02214076×1023. It is expressed with N or NA. The value can be rounded up to 6.0226×1023.

This value is insanely larger than it looks. Let’s write it without using the scientific form.

602,214,076,000,000,000,000,000- That’s 602 sextillion or two times billion.

There is no analogy that you can easily imagine and understand. Suppose, the earth was completely made up of softballs. The seas, mountains, buildings, everything. The number of softballs you would need is Avogadro’s number.

Or suppose, you stacked 1 mole of papers. Paper sheets are very thin. So how high will the stack be? Any guess? If your answer is up to space then you are not right. The stack will reach space and beyond. It is so high that it will go up to the moon and back 80 billion times. How big is that!!

Now imagine 6.02214076×1023 water molecules. How much would that be? Hold tight, it’s about the amount you drink in a sip.  That is 18 mL of water. No need to worry, atoms are that small. It’s a perfect contrast.

It would take 20 drops of water to form a milliliter. Just think, for each drop of water people waste, 1.67 x 10^21 molecules of water are wasted.

Never waste even a drop of water.

The Mole

As said earlier, it is not the furry earth animal, it is a unit. Specifically, a counting unit.

It is defined as the amount of substance that contains 6.02214076×1023 number of atoms, molecules, ions, particles, or any entities is called a mole of that substance. It is expressed with n. It can also be abbreviated to mol.

But 6.02214076×1023 is Avogadro’s constant. So, do you get it now? A mole is any amount that contains Avogadro’s number of particles.

The mole is similar to the dozen. Let’s see,

1 dozen apples= 12 apples

1 dozen eggs= 12 eggs

So, 

1 mole apples= 6.02214076×1023 apples

1 mole eggs= 6.02214076×1023 eggs.

It is as simple as it looks.

Now let’s see how the mole relates to the mass of a substance. As you’ve already seen, the mole is defined in a way so that the mass of a mole of any substance is the same as the relative mass expressed in gram. So, 

1 mole of carbon= 12g carbon 

1 mole of aluminum= 27g aluminum

And this mass of 1 mole of any substance is called the molar mass of that substance which has the unit gmol-1.

Thus, you can say,

number of moles (mol), n=mass of substance in grams gmolar mass g mol–1

or n= mM

You must have thought many times by now, “Why is mole so important?” It’s because most of the measurements in chemistry are done in terms of moles. The mole can at the same time relate both the mass of the substance and the number of atoms or molecules. Also, chemical substances react in terms of numbers and the mole represents a whole number. So, the mole is also used in expressing reactions and plays a great role in quantitative chemistry. 

It’s common knowledge that 2 atoms of hydrogen react with one atom of oxygen to produce 1 molecule of water. Now, this can be also said in terms of mole.

2 mol hydrogen + 1 mol oxygen= 1 mol water.

H2 + 12 O2 = H2O  [Hydrogen and oxygen are diatomic gases]

You don’t get much information using only numbers of atoms. But from this mole equation, we can immediately know,

2g hydrogen+ 16g oxygen= 18g water

The benefits of using the mole unit are way more than this.

Let’s do some mathematical problems involving the mole now.

How to calculate the mole numbers of a given amount of substance

The equation that relates the mole and mass of the substance is, 

number of moles (mol), n=mass of substance in grams g, mmolar mass g mol–1, M

Note that the mass of the substance has to be in grams. And you already know that the molar mass is basically the relative mass expressed in grams or in this case, gmol-1.

Problem 1: Use these Ar (relative atomic mass) values (Fe = 55.8, N = 14.0, O = 16.0, S = 32.1) to calculate the amount of substance in moles of 10.7 g of sulfur atoms

Solution: 

Molar mass of sulfur atoms= 32.1 gmol-1

Mass of given sulfur atoms= 10.7 g

So, number of moles= 10.7 g32.1 gmol-1

   = 0.33 mol

Suppose, what’s given is the number of moles and you are told to determine the amount of substance, how would you do that? Have you already figured it out? Yes, you just need to rearrange the above equation. After rearranging we have,

Mass of substance in grams (g)= number of moles (mol)×molar mass (gmol-1)

Problem 2: Calculate the mass of 0.050 moles of sodium carbonate, Na2CO3 (Ar values: C = 12.0, O = 16.0, Na = 23.0).

Solution: Molar mass of Na2CO3 = (23×2) + 12 + (16×3) gmol-1

 = 106 gmol-1

Number of moles= 0.050 mol

Thus, mass of 0.050 moles of Na2CO3= 106 gmol-1 × 0.050 mol

         =5.3 g

Pretty easy, right?

With this, our discussion ends today. If you liked the content, please visit our website for learning more about chemistry.

Have a good day!!

The post The Mole and Avogadro’s Constant appeared first on Chemniverse.

The Building Blocks: Atoms and the Periodic Table

Atoms are the basic units of all matter. Atoms consist of protons, neutrons, and electrons. The protons and neutrons reside in the center or nucleus of the atom, while electrons orbit around the nucleus. The number of protons in an atom determines its identity or element type on the periodic table of elements.

The periodic table orders the elements by increasing atomic number from left to right and top to bottom. It groups elements into broad categories of metals, nonmetals, and metalloids. The vertical columns or groups share certain qualities and reactivity trends.

The horizontal rows or periods indicate the number of electron shells. Common groups discussed in introductory chemistry include the alkali metals, alkaline earth metals, halogens, noble gases, and transition metals. Gaining familiarity with the groups and periods can help predict chemical behaviors of different elements.

Ionic and Covalent Bonds

Atoms form bonds or links with other atoms through the transfer or sharing of electrons. The electrons in the outermost shells are called valence electrons. An ionic bond results from the electrical attraction between positively and negatively charged atoms or ions after the transfer of valence electrons. Ionic compounds are typically formed between metals and nonmetals.

The atoms unite in ratios that produce neutral compounds. By contrast, covalent bonds involve the sharing of pairs of valence electrons between two atoms. The atoms in covalently bonded compounds usually have similar electronegativities or attractions for electrons. The bonded atoms attain a stable electron configuration similar to that of noble gases by sharing electrons. The degree of polarity in a covalent bond depends on how evenly the bonding electrons are shared between atoms. Polar and nonpolar covalent bonds manifest in different compound properties.

Chemical Reactions, Balancing Equations, Acids and Bases

Chemical reactions and equations demonstrate the rearrangement of atoms caused by breakage, formation, and reformation of chemical bonds. The reactions have definite quantities known as stoichiometry which serve to balance equations.

The reactants (starting materials) and products (resulting substances) are separated by an arrow. Coefficients are added before chemical formulas to satisfy the law of conservation of mass and balance the atoms. Acids and bases are important compound types that dissociate or ionize in water to release, respectively, excess hydrogen ions (H+) which lower pH and hydroxide ions (OH-) which raise pH.

Strong and weak acidity depends on the degree of dissociation and release of H+. Neutralization reactions between acids and bases result in salt and water formation. Understanding balancing equations and the behavior of acids/bases has many practical applications.

States of Matter

Matter exists as solids, liquids, gases and plasma. The states have notable distinctions. Solids have definite volumes and shapes from the close arrangement of particles. The more tightly bound particles vibrate in fixed positions but do not otherwise move freely. Liquids have definite volume but not shape.

Their particles move more freely past each other but are still closely packed. Gases have no defined volume nor shape as the particles move completely freely and are highly dispersed. Changes of state are explained by kinetic molecular theory. Adding or removing heat energy impacts the kinetic energy and motions of the particles.

Solids liquefy into liquids with added heat while liquids vaporize into gases with more addition of heat. The changes between states are indicated on heating and cooling curves. Understanding phase changes and associated energies is important across scientific disciplines.

Importance of Chemistry Concepts

Building knowledge in fundamental chemistry prepares you for more advanced study across the physical sciences and supports greater scientific awareness. Understanding atoms, elements, periodicity, bonding, reactions, acids/bases, and states of matter will help you better comprehend many important processes from materials properties to biological functions to the environmental phenomena you encounter everyday.

With foundational knowledge, you can move on to expanding your learning into subjects like nuclear chemistry, thermodynamics, organic chemistry, biochemistry, atmospheric chemistry and more while appreciating how these concepts tie together. Mastering chemistry basics equips you with scientific literacy to make informed decisions and allows you to fully appreciate the central, essential role chemistry plays in our world.

The post Basic Chemistry fundamentals-Your Guide to Core Concepts appeared first on Chemniverse.

When you hear the word metal, the picture that comes to mind is of something rigid, shiny, and cold object used in building large sturdy structures. Or do you think about the liquid metal cooling in the latest PS5? If not, then you might think of iron, copper, or steel. Yes, that’s the general picture of metals. But they are substances which can have three physical states. Have you ever thought of metals in their liquid form? If you did, it is probably in their hot molten, and glowing state.

But opposing that concept, certain few metals can also be found in their liquid state at normal temperature. Note that, in chemistry room temperature means 25 ˚C. But in general terms, it can have a wide range. So, metals that melt at a slightly higher temperature were also included.

The question comes to mind, why are they different? To know the answer, we have to know about metallic bonds, the bond between metal atoms. Here is a brief description. 

Metallic Bond

The characteristic of metals is just so that they neither completely give up nor hold in their outer shell electrons. As a result, their atoms create a matrix where they form positive ions and are surrounded by electrons. Think of a chunk of metal. In that chunk, there are numerous metal ions submerged in a sea of electrons which are loosely bonded to their atoms.

Those who have a slightly stronger attraction to electrons produce stronger metallic bonds and thus are solid at normal temperature. Most of the metals are this way. But a few have so little attraction that they produce very weak bonds and thus easily melt at normal temperature.

[If you want to know more details about the metallic bond, do not delay and check out our website]

Let’s stop talking about metallic bonds already and check out the very interesting stuff that liquid metal is.

Fireworks are one of the most beautiful things made by humans. But did you know that the colors of it are due to metal salts? One such metal is rubidium which is used to produce violet-red colored fire. And it is also one of the metals of today’s topic.

5. Rubidium (Rb)

Rubidium (Rb) is an alkali metal of the 5^th period with an atomic number of 37. It is just below the potassium in the periodic table. It has a melting point of 39.3 ˚C (102.74 ˚F), a bit above our body temperature. It is not found readily in its liquid form but if you consider countries with a very hot climate you may find it in the liquid state under normal condition. Thus, rubidium was able to make a place for itself in the list of metals that are liquid at room temperature.

When not in liquid form it is so soft that you can easily cut it with a kitchen knife. It has a common silvery-white appearance. The name rubidium originates from the Latin word rubidius, which means deep red. You might be thinking, how in the world red and rubidium is related. It is because the atomic spectrum of rubidium has unique red lines. Although rubidium is not that well known and does not have that much use, it still has few very important uses. 

The color of the flame of rubidium chloride (RbCl) is violet-red and so it is used in fireworks to produce beautiful violet colors. Fireworks are short-lived. But the isotope rubidium-87 has a half-life of 49 billion years which is 3 times the age of the universe. You may forget the sense of time while looking at beautiful fireworks. So, you would want to look at your clock to check the time. While you are happy if your clock is accurate to minutes, scientists need clocks that are more sensitive and accurate. And the isotope rubidium-87 does just that. It is used in atomic clocks due to its extremely high accuracy. Rubidium is also used in treating depression.

Even though rubidium sounds so good you must be careful around it. It is the second most electropositive metal on earth. It is so reactive that it will self-ignite in open air by reacting with atmospheric oxygen. It also reacts explosively with water. For this reason, rubidium is stored in an inert atmosphere or submerged in dry oil e.g., kerosene.

Enough with rubidium. Let’s check out our next liquid metal.

4. Gallium (Ga) 

Gallium (Ga) has a melting point of 29.76 °C (85.57 °F). Although like rubidium it also has a melting point above room temperature, it is not that high. And it even melts in your hand. So, gallium’s position in this list is well deserved.

The phrase “melts in the mouth” is just perfect for this element. Wait, don’t try it. Gallium is not toxic in a small amount. But there is little knowledge. Guess, it doesn’t taste that good then. Still don’t try it.

Gallium sits just below aluminum in the periodic table with an atomic no of 31. And has a silvery-white appearance. Its discoverer, Paul-Emile Lecoq de Boisbaudran named it after the Latin word ‘gallus’ meaning ‘Gaul’ which is the old name of France, his homeland. Although some believed he named it after himself as both gallus and Lecoq mean rooster, this idea was denied. 

Like aluminum, it has also proven its importance through many uses. When someone gets a fever, what you do first is to measure the temperature using a thermometer. What has gallium got to do here? You have guessed it correctly. Gallium is used in thermometers instead of mercury. Mercury is toxic whereas gallium can melt in the mouth. I would definitely choose gallium over mercury.

There are many other substances that can be used in thermometers. But gallium can do much more. At this age, there is no way you have not heard about semiconductors. Yes, gallium is one of the very few elements that is used to produce semiconductors. If you have a computer, you probably know what a solid-state drive is. The successor of hard-disk drives which are many times faster and more durable while much smaller. Don’t be surprised. Gallium semiconductor is used to make those fast storage devices. 

Not everyone likes techs and things like these. But they sure do like to watch a good magic trick. Or even better, do a magic trick and get everyone’s praises. And gallium can help you do just that. Want to know how? A magician never reveals his secret. But hey I am no magician. The trick is called the vanishing spoon trick. For this, you need a spoon made of gallium metal. Act as if you are making tea for your friends and now stirring the warm tea with a ‘spoon’. Voila, the submerged part of the spoon is gone. Isn’t it fun to look at friends’ stupefied faces? 

Is that you, T-1000?

Not only this, gallium is used in a fun experiment called beating heart where it literally beats like a living thing. Science sure is fun and interesting and of course amazing. Won’t you agree?

Ah, there is one more important use of gallium which is to make alloys, solid solutions. As gallium is liquid it can easily dissolve a lot of other metals. Try putting gallium on a soda can. Be sure to remove any paint coatings. And see the magic.

There are many more fun and important uses of gallium but others are waiting in line.

So, let’s hurry and move on to our next metal on the list.

3. Cesium (Cs)

(IUPAC name – Caesium)

Our next metal in the list, the one that has been hailed as the most electropositive element on earth, is none other than cesium (Cs). It has a melting point of 28.5 °C (83.3 °F), which is almost equal to that of gallium. But don’t ever try taking it even in your hands. You will know why in a bit. It has atomic no 55 and has the 2^nd lowest position in group-I which is just below rubidium. As a metal from the same group, it has lots of similarities with rubidium. They are just like brothers. The name cesium comes from the Latin ‘coesius’ which means sky-blue. Like rubidium, cesium got its name from the color of atomic spectral lines which are blue. But unlike other group-I metals, it has a pale gold appearance.

As you have read earlier, cesium and rubidium are like brothers but cesium is like the older one. More ductile, more reactive, more electropositive, and thus more hazardous. The explosions it creates while reacting with water is so violent that it can even break the vessel if it is made of glass.

And yeah, cesium too is used in atomic clocks, specifically, the cesium-133 isotope is used. But it is more accurate. In fact, it is the most accurate measurement humans have ever achieved. This fact is a lot more than it sounds. It has so little error that it would take 20 million years for a cesium clock to deviate by just 1 second. How cool is that!!

Not just that. The very unit “a second” is defined in terms of cesium! The time it takes for cesium to complete 9 192 631 770 ground-state transitions is equal to one second. Imagine, for every second that passes, a cesium atom vibrates 9 192 631 770 times.

Cesium has four isotopes among which only cesium-133 is stable while others are radioactive. And the use of cesium mostly involves its radioactivity.

You saw that the melting point decreases as we go down the group-I metals. And cesium is the 2^nd lowest metal. So, shouldn’t the lowest metal have an even lower melting point? And yes, our next metal is francium, the last member of group-I.

2. Francium (Fr)

Francium was discovered in France by Marguerite Perey in 1939 and was named after the country. It is situated in group-I, period-7 In the periodic table. Just below cesium.

It is the second rarest naturally occurring element on earth. It is radioactive and has a very short half-life. Even the most stable isotope francium-223 has a half-life of only 22 minutes. It is naturally produced through the decay of actinium but itself decays into astatine, radium, and radon. It is found in trace amounts with uranium ores. Believe it or not, you can find only about an ounce (20-30 grams) of francium in the earth’s crust at any given time but that would also decay. And only a few hundred thousand atoms were synthesized by humans. You would have to pay billions of dollars only to get a few grams of this substance. And so, not much about francium is known. 

It has a melting point that is uncertain and estimated to be 8.0 °C (46.4 °F). You may think that francium should have been the most electropositive metal instead of cesium. But it has been predicted that its radioactivity might interfere which on contrary will lower the electropositive nature.

 Being so rare, it has no commercial applications. It has been used in scientific research only.  Scientists also tried to apply it in cancer diagnosis but it was found to be impractical.

We might not know a lot about francium. But our next and last metal has been familiar to humans since a long time ago. And it is none other than mercury.

1. Mercury (Hg)

Mercury is the top liquid metal on earth. It is the only metal that is liquid at standard temperature and pressure (0 ˚C, 1 atm). It has a melting point of −38.82 °C (​−37.89 °F) which, as you can see, is way lower than even water. 

It is a transition metal with an atomic number 80 and an atomic mass of 200.592. It has a shiny silvery appearance and so it is also called quicksilver. It is named after planet mercury due to its high speed. The Latin name of mercury, hydrargyrum, comes from the Greek word hydrargyros which literally means water-silver.

Although mercury is not very reactive and does not react with most acids, it is very toxic for humans and other animals. It accumulates in the body and causes various diseases and mercury poisoning. But It has a lot of uses in our daily life.

Mercury was familiar to humans since as early as 1500 BCE. And still is heavily used. It might surprise you, but it is a rare metal. The major source of mercury is cinnabar, an ore of sulfur (HgS) which is also called red mercury because of its color.

When you hear mercury, you probably think of a thermometer. As you already know mercury is liquid under normal conditions. And luckily, its volume changes uniformly with temperature which makes it a suitable material for thermometers. But it has a lot of other uses. The ancient people produced red pigment called vermillion using cinnabar. And It was of great importance in alchemy. Although it might shock you, mercury was therapeutically used until as late as the 18^th century. More shocking, people believed that drinking mercury prolongs life which on the contrary caused them an early death. Ironic, isn’t it?

Although in decline, mercury is used a lot. The first thing that comes to mind after the thermometer is the air pressure. Atmospheric pressure is also expressed in mmHg units ( 1atm=760mmHg). And thus, mercury is used in the barometer, the device used to measure the pressure of atmospheric pressure. It is used in making fluorescent light also known as neon signs. The major use of mercury is in the PVC industries of China. And it is China that is the major supplier of mercury. You have already read about atomic clocks. The fact that they are super accurate is amazing but the downside is their large size. Accuracy of time is very important in space for astronauts and other spacecraft. Luckily NASA has developed an ultra-precise miniaturized atomic clock using mercury which albeit not as accurate as of the cesium clock, is much smaller. 

You might have already guessed that liquid metal mercury must have contributed to producing alloys (metal solutions). You are right. Mercury forms amalgams, Meaning alloys of mercury, with almost all metals except iron. You can even extract gold using mercury as a solvent. An interesting fact is that mercury is not allowed to carry on planes because of how easily it forms an amalgam with aluminum, the major component of a plane’s structure. Did you already know that? Well, now you know. If you know someone who likes sweets and candies too much and unfortunately caused cavities, you might know dentists use a type of paste as filling. Don’t be surprised, mercury is used to make that paste. 

All the known forms of mercury are harmful and toxic. We now end this list wishing you to be safe from harmful chemicals.

But before going let’s know a bit more about liquid metal in general. Although the existence of liquid metal has been known to humans for a long time, this property has been mostly used for producing alloys and nothing much. But now more work is being done on this property. You might have already understood that common properties of metal such as conducting heat or electricity would not be the same for the liquid state. The liquid metal processor coolers for high-end computers or the latest model of PlayStation, PS5 are just the beginning.

With the desire to serve more interesting and amazing content, Goodbye!!

The post The Only 5 Metal Elements on the Periodic Table which are Liquid at Room Temperature appeared first on Chemniverse.

Before talking about subatomic particles, let’s know what an atom is. Atoms are the building blocks of matters. It is the smallest unit of an element retaining its properties.

Democritus was the first to propose that all matters were made up of indivisible particles called atoms. The word, “atom” comes from the Greek word, “Atomos” which is divided into, “a” and, “Tomos”. “A” means, “not” and, “Tomos” means, “to cut”. Thus combined, “atom” means “uncuttable” or “indivisible”.

 Suppose, if you were to break your phone (do not do it actually), you will see different parts that made up the phone. Now, grind it, and it will turn into very small particles. You can tell by looking at or touching what those originally were- plastic, metal, etc. and you can isolate these particles individually. Let’s not stop here and grind this even more and more. How much far can you go? By normal means, this process can’t go past a point. But, hypothetically, if you keep dividing those particles, you will reach a point that dividing it will make the particles lose their properties and you will be left with elementary particles and that is the smallest possible unit. In this case, carbon, hydrogen from plastic, copper, other metals, and silicon, oxygen from glass, etc. We are down to a scale that can’t be seen even with the strongest of microscopes. If you were to put 10 million hydrogen atoms in a line, it will only be 1 meter long. 

And this is what you can call an atom.

Particles in an Atom

But things don’t end here. People started to wonder if this is unbreakable or is it made of even smaller particles. And the answer is, “Yes”.

An atom is made up of about 200 different types of particles such as proton, neutron, electron, muon, positron, tau, and blah blah blah. These are called subatomic particles. Among these only protons, neutrons, and electrons are permanent and contribute to the structure of the atom while the others act as force carriers and not permanent. You can compare the protons, neutrons, and electrons to bricks, rods, and cement. And other particles can be compared to paints, tiles, or such.

Many scientists have worked hard to discover the structure of the atom. Particularly, Rutherford’s alpha-particle scattering experiment’s contribution is noteworthy.

Primarily, an atom can be divided into two parts: 1. The nucleus and 2. Electron orbits. Protons and neutrons make up the nucleus of the atom while electrons move around the nucleus in certain orbits. Protons and neutrons are also called nucleons as they make up the nucleus. Let’s elaborately talk about the atomic structure some other say. Today is for subatomic particles only. 

If are very much shocked about the fact that atoms can be divided then hold tight. There is an even bigger surprise for you. Even the particles proton and neutron can be divided. They are composite particles meaning they are made up of even smaller particles.

A proton is made up of two up quarks and one down quark while a neutron is made up of two down quarks and one up quark. The quarks themselves are elementary particles and so is an electron. There are mainly six types of quarks in the universe.

Electrons

One of the blessings of the modern world is electricity and electrons are the particle that carry it through wires. It is one of the twelve elementary particles meaning it can’t be divided anymore. Electrons were first discovered by J. J. Thompson in the year 1897 through the cathode tube ray experiment. He passed high voltage electricity through a vacuum tube. When electricity flows, a ray is produced known as the cathode ray. This ray was attracted to a positively charged plate placed on the tube. Later it was discovered that this ray was, in fact, a flow of negatively charged particles named, “electron” by J. J. Thompson. 

Electrons are denoted by, “e”. It has a mass of 0.000549 a.m.u. or 9.11×10^-31 kg and it has a charge of – 4.8×10^-10 e.s.u. or – 1.6×10^-19 C. An electron is almost 1836 times lighter than a proton.

Protons 

Protons are positively charged particles that can be found in the nucleus of an atom. Protons were discovered by Rutherford in 1917. In the year 1886, German physicist Eugen Goldstein discovered a positively charged ray in gas discharge which travels in a direction opposite to the cathode ray. He named them, “Canal ray”. This beam consists of positively charged ions. Using this the charge-to-mass ratio of various positive ions was calculated. It was then proved that the hydrogen ion had the smallest size among all ionized gases of elements.

In 1911 Rutherford conducted his alpha-particle-scattering experiment and concluded that all the positive charge of an atom was concentrated in the center of an atom and named it nucleus. He also observed that hydrogen nuclei were produced when the alpha beam was shot through the air. After investigation, he proceeded to bombard nitrogen gas with alpha particles which produced a greater number of hydrogen nuclei. He concluded that the hydrogen nucleus was a part of all the atoms and named it proton.

Protons are denoted by, “p”. As a hydrogen nucleus without an electron is but a proton, it is also expressed as H⁺.

The mass of a proton is 1.007 a.m.u. or 1.6725×10^-27 kg. It has the same charge as an electron but opposite i.e., 4.8×10^-10 e.s.u. or 1.6×10^-19 C.

Neutrons

Neutrons are as the name suggests, electrically neutral particles. They make up the nucleus along with protons. British physicist Sir James Chadwick was the one to discover neutrons in the year 1932. After the alpha-particle scattering experiment, Rutherford had already predicted the existence of a neutral particle. It was then known that the atomic number was the number of protons in the nucleus. But atomic numbers and relative mass were different. So, where did this extra mass come from? In 1913 isotopes were discovered which raised more questions about the difference in mass. It was thought that there were excess protons in the nucleus, with an equal number of electrons to cancel out the additional charge. But there was no evidence.

In 1928, German physicist Walter Bothe and Herbert Becker found out that if alpha particles emitted from polonium is incident on beryllium, it gives off a penetrating and electrically neutral radiation. This radiation was interpreted as high-energy photons.

But then something interesting happened. In 1932, Irene Joliot-Curie, one of Madame Curie’s daughters, and her husband, Frederic Joliot-Curie, studied the then-unidentified radiation from beryllium for further investigations. They found that this radiation ejected protons of high velocity from a paraffin target. They tried to associate with the Compton Effect. Here Compton Effect is a phenomenon, where, if photons with high enough energy are incident on a metal surface, they knock out protons from the metal. The Compton effect was observed by Arthur Holly Compton in 1923 and was named after him.

Now, the problem is that protons are about 1836 times heavier than electrons. Yes, an ant might be able to carry weights six times their own, but imagine an ant trying to knock away an elephant. So, the neutral beam being a high energy photon is quite unlikely. 

This is where Sir Chadwick comes in. He could not accept Compton Effect as the conclusion and tried similar experiments with other elements in addition to the paraffin wax, including helium, nitrogen, and lithium as targets. By measuring the kinetic energies of ejected protons, he found out that the beryllium emissions contained a neutral component with a mass approximately equal to that of the proton and named this particle neutron.

He won the Nobel Prize in the year 1935 from Physics for this discovery. Though the Juliot-Curie pair missed their chance of getting a Nobel prize, in this case, they got a Nobel prize for discovering artificial radioactivity. So, there is no reason to feel sorry.

But this is not the end. For all we know, there might be other particles playing hide and seek only to be found by you. By the way, the Nobel prize is worth about 1.5 million US dollars .

The post Subatomic Particles In An Atom: Their Discovery and Properties appeared first on Chemniverse.