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Showing posts from January, 2013

Phosphorous : The bringer of Light

Man invented fire ages ago and till date, fire is an indispensable aspect of our everyday life. Right from cooking to light, we use fire directly or indirectly. We use matchsticks for lighting the lamp and also for many other things. The matchsticks have phosphorus and let us now find out more about phosphorus....  Phosphorus: The Bringer of Light Ever since man discovered fire, it has been an indispensable aspect of our everyday life. Wondering what phosphorus has to do with fire? Keep reading... Let there be Light (Phosphorus) Phosphorus has the ability to ignite readily and hence is used as the main constituent in the heads of matches. It smoulders in air, and when it is warmed, it bursts into flames thereby producing thick, acidic smoke. In the late 17th century, a German alchemist named Hennig Brandt heated the solid residue that was formed by the evaporation of urine. The distilled vapour glowed in the dark. As a result of this observation, Brandt named his

Why does a kitchen gas burner glow yellow when liquid comes in contact with it?

If you have been in the kitchen when your mother boils some water or milk, you may notice the flame of the gas burner turns yellow when liquid comes in contact with the flame. Did you know that there is chemistry at work behind this? The story of sodium ions A natural gas flame is yellow because of burning sodium atoms or ions. Water consists of salt dissolved in it. Common salt is sodium chloride. This is why you may notice that water that falls on the burners grill and evaporates leaves a white residue left on it. This white residue is salt. At the same time the sodium ionizes releasing photons that give the yellow. You may have also seen this yellow emission of sodium atoms in sodium lamps, which produce yellow light due to this reason. Even the tail of the Hale-Bopp comet is yellow for the same reason. The colour of a flame The colour of a flame is also determined by the oxygen that is available to it. You may see that in your school chemistry lab the B

The sticky truth about Adhesive tape

Adhesive tape is a tape that is coated with adhesive either on one side or both, and used for temporarily or permanently joining two overlapping materials. Adhesive tape is something we all use in our daily lives. It serves a number of purposes. Its convenience makes it virtually indispensable in our homes and while at work. If for example, you accidentally tear an important document at work, you reach for an adhesive tape to fix it in a jiffy. Though this invention has become indispensable in our lives, have you ever thought about what is the science behind this invention? History of adhesive tape Natural adhesives like beeswax, resin and bitumen have been used for a long time. The ancient Egyptians used glue made from animal skin and bones for woodworking. Medieval monks used egg white to bind gold leaves to their illuminated manuscripts. The 19th century saw the advent of rubber and pyroxylin cements. Adhesive tape was invented in 1925 by American inventor Richar

Carbon Monoxide : Useful but Deadly

When we say the word "carbon monoxide", the first thing that comes to our mind is pollution and dangerous diseases that are associated with it. Let us find out more about this otherwise harmless molecule..... Carbon Monoxide: Useful but Deadly The word "carbon monoxide" is associated with deadly diseases and pollution. However, in reality, it is a simple molecule that regularly gets a bad reputation in the press! It is in fact quite useful in many parts of the chemical industry. Let us reintroduce you to Carbon Monoxide Carbon monoxide is a very versatile element and forms the basis for all of organic chemistry. It is the main greenhouse gas and is constantly monitored by pressure groups throughout the world. Carbon monoxide is made up of molecules containing one carbon atom and one oxygen atom. Both of these atoms join together with a multiple covalent bond . The molecule formed as a result is used to make useful chemicals such as aldehydes,

The history behind your eraser...

An eraser is an instrument of stationery used to remove pencil and sometimes pen marks. It is rather interesting to know that before the invention of erasers slabs of wax and breadcrumbs were used to 'wipe out' charcoal or lead marks from paper. Can you imagine doing that in the classroom? The first pencils were discovered around 1560's but people did not have anything that could rub out the marks with. The first erasers The history of the first erasers dates back all the way back to 1770 when Joseph Priestley discovered a vegetable gum that possessed the ability to 'rub out' pencil marks. Quite similarly, in the same year, Edward Nairne, an English engineer discovered rubber's erasing properties. This was the first practical use of the substance in the whole of Europe. When the facts don't stretch It was noticed that while the rubber softened in warm weather, it became hard in cold conditions. What 's more, the first rubbers had an

Why is sulphuric acid called the king of chemicals?

What's common to petrol, fertilizers, cars and soaps? They, like a lot of other things, require sulfuric acid to be made. That's why sulfuric acid is called the king of chemicals. The uses of sulfuric acid Sulfuric acid is involved, in some way or the other, in the manufacture of practically everything. Indeed, the production of sulfuric acid is sometimes used as a measure of how industrially advanced a country is. India produces about 48 lakh tonnes of this acid a year. 60% of all sulfuric acid produced is mixed with crushed phosphate rock to make phosphoric acid. Phosphoric acid has two uses - to make phosphate fertilizers, and to make sodium triphosphate, which is a detergent. Lots of sulfuric acid is used to clean up rust from steel rolls. These cleaned up rolls are used to make cars, trucks, as well as household appliances. Sulfuric acid is used in petroleum refining to make high-octane petrol, which burns efficiently. It is put in the lead-acid batter

Potassium Permanganate : The all rounder salt

If you've seen a well being cleaned, you may have noticed that a reddish brown powder is thrown into it. That would be potassium permanganate, which is one of chemistry's most useful substances. The germ fighter Potassium permanganate is a strong oxidising agent when dissolved in water. KMnO 4 + H 2 O → MnO 2 + K + + OH - + O * The oxygen free radical is a powerful toxin, and kills off bacteria and fungi. That's why potassium permanganate is used to clean not just wells, but also fish tanks, water storage tanks, water pipes etc. You can use a dilute solution of KMnO 4 (which is pinkish red in colour) to treat mild skin infections, bruises, sores etc. But don't ever use it on cuts or deeper wounds. If you keep an aquarium, you can use a very mild solution to keep your fishes free from bacteria. It is used in laboratories, poultry farms and hospital wards as a fumigation agent to kill fungi. During fumigation, the cleaner puts one gram of potassium

Discovering Carbohydrates

Carbohydrates are organic compounds of carbon, hydrogen and oxygen. The proportion between the hydrogen and oxygen in this is the same as it is in water. Plants produce carbohydrates by the process of photosynthesis. The importance of carbohydrates Carbohydrates are an important part of our daily lives. They are present in most of the food that we eat in the form of starch and sugars. And that’s not all! Carbohydrates are also part of the clothes you wear. A carbohydrate called cellulose is part of cotton and linen. What’s more this cellulose is also present in the wood that we use to build houses. So carbohydrates are also responsible for the roofs over our heads! Carbohydrates can be classified into monosaccharides (the simplest form of carbohydrates), disaccharides, oligosaccharides and polysaccharides (which are long chains of monosaccharides). Classification of carbohydrates Carbohydrates can be classified into monosaccharides (the simplest form of carboh

What makes perfumes smell nice?

When your mom is going to a party, you'll have seen her spray on some expensive perfume. Why does she do this? What's the secret in the bottle? What exactly is a perfume? Let's take this in two parts. First we'll talk about what goes into a perfume. And then we'll see what effect it has on us. What women put on is called a perfume, while men put on fragrances. What's the difference? Well, perfumes are mixtures of many chemicals (called notes), while fragrances are much simpler. The chemicals used in a perfume or fragrance are called essential oils (better known as essence). All of these can evaporate very quickly when left open, and are generally gotten from the leaves or flowers of plants. For example, limonene is an essential oil that comes from lemon leaves and gives the familiar 'lemon' smell. Essential oils for making perfumes are extremely expensive, and were among the things for which traders would go any length. They form

The sparkling truth about Diamonds

Diamonds are always called a girl's best friend. They are formed from carbon and are used for a variety of purposes from jewellery to use in lasers and cutting and polishing tools. Though most diamonds are colourless you do come across a few; rare coloured diamonds. What are diamonds? Diamonds derive their name from the Greek word for unbreakable - adamas. They are the hardest, naturally occurring substance on the planet. Diamonds are one of the several allotropes of carbon. Diamond is considered less stable than graphite. The chemical makeup of diamonds ensures that they have very few impurities, making them ideal for optical applications. They are also excellent conductors of heat. So if you ever place a large diamond in your mouth it would be quite cool to feel. Place a large diamond in your mouth and it would feel quite cool being an excellent conductor of heat. How are diamonds formed? When deposits of carbon are exposed to high pressure and temperatu

Career Prospectus After M Sc. In Chemical Science.?

Career Prospectus After M Sc. In Chemical Science There are many job opportunities available in the public and private sector for candidates who have completed their Master's in Chemistry. Central Government Jobs after M.Sc in Chemistry 1. There are many research institutes in our country that require professionals in the field of chemistry. The ISRO, DRDO, Bhabha Atomic research Centre (BARC), Advanced Centre for Treatment, Research and Education in Cancer etc. take students from M.Sc. Chemistry very frequently via national level entrances with lucrative salaries. 2. On top of this, the UPSC, CSIR – UGC, SSC etc. carries out entrance exams for the recruitment of qualified candidates into the various departments of the government as Scientists . 3. In addition to this candidates with M.Sc. Chemistry can also appear in the Civil Service exams and state PCS where a sound background in chemistry provides an edge. 4. It is also possible for them to join petroleum

Why do we detect odor when LPG leaks?

Your mother might have warned you many times to tell her if you ever get a pungent smell from the kitchen. The smell might have been from a gas leak. Read on to know what it actually is. And what you should do when you detect a leak. What is natural gas? Natural gas is an odourless gas. It consists of several gases that occur naturally under the earth’s surface. This gas consists of compounds made of two elements of carbon and hydrogen called hydrocarbons. The most common gas in natural gas is methane. Natural gas is considered to be the safest form of energy. This is because the gas itself is not toxic and it is easy to discover when there is a gas leak. What is that bad smell? The red cylinder you see in your kitchen contains the natural gas that’s used for cooking called Liquefied Petroleum gas (LPG). Sometimes, due to an accident or if the valve is not closed properly, the gas from it may leak. If natural gas is odourless, then how do you smell a LPG leak?

Always under attack by mosquitoes..?Find out why!

Do you consider yourself sweet-blooded just because mosquitoes attack you more than others? Well, people may call it just your imagination to rule it out, however that is not right. Mosquitoes really have their preferences and may find one target more attractive than the other. Always under attack by mosquitoes? Find out why! The moment the sun sets, you panic and start closing all the windows of your house to keep the mosquitoes out. And even though there are other people living in your house, the mosquitoes always come looking for you! It's true that they really do have a preferences and find one target more attractive than the other... Why do you attract them? Mosquitoes with their highly sensitive chemical receptors can spot their victims almost from a distance of 100 meters. It is always the female mosquito that bites us in order to suck our blood to nourish her developing eggs. They find their targets with visual, heat and some chemical sensors. If your

Indoor Pollution: The Dangers at Home

It is so refreshing to get back inside the house after a tiring day, leaving behind the noise, air and light pollution of the traffic. But did you know that pollution is as serious a problem indoors as it is outdoors? The Unseen Dangers As cities grow, buildings have become more crowded, with stuffy rooms and poor ventilation. Because of this, many pollutants get trapped in the indoor air and their concentration increases over time. Let's have a look at some pollutants. Fossil Fuels: Whenever you cook food at home, some of the LPG gas you use escapes unburnt. LPG contains gases like hydrocarbons, carbon monoxide and nitrogen oxides. Though released in quantities that are too tiny to detect or cause immediate harm, over time these gases can accumulate due to poor ventilation. Lesser fortunate families that use kerosene or firewood face even greater dangers. These pollutants can cause asthma, heart disease and cancer. Smoking: It is sad but true that many people s

All about natural mosquito repellents

We have always known mosquito repellents to carry pungent and irritating smell. In fact, many of us are even allergic to the smell because of the chemicals involved in these repellents. However, we do have natural mosquito repellents that are not pungent and are user friendly... Let us explore more... All about natural mosquito repellents Wonder why mosquitoes always attack you and not your friend wearing fewer clothes? Mosquitoes have complex methods of detecting hosts. Different types of mosquitoes react to different stimuli and you can avoid being bitten by making sure that you are not attracting them. Here is all that you need to know about mosquitoes and how to avoid them next time! What makes you so attractive to them? Dark Clothing - Most mosquitoes use vision to locate their hosts from a distance. Dark clothes and foliage are initial attractants for the mosquitoes. Carbon Dioxide - Mosquitoes generally get attracted to people who discharge more CO2. So

A Tale of Vinegar and Hard Water

If you live in an area where the water is hard, you may notice that when you wash utensils, a thin white stain is left behind. Did you know you can use vinegar to remove these stains? What is hard water? Sometimes, the water that you get from wells looks a little cloudy and tastes odd. This is called hard water, because it has many insoluble salts mixed in it. Water without such salts is called soft water. Water in the ground has many ions dissolved in it, including sodium, calcium and magnesium. When the water comes to the surface, it dissolves some carbon dioxide from the air. The carbon dioxide reacts with the dissolved ions to form their respective carbonates. While sodium carbonate dissolves readily in water, calcium and magnesium carbonates do not. They remain present in the water as a fine suspension. You find hard water mostly in coastal and limestone-rich areas. Insoluble deposits Where soft water is rare, people use it for bathing and cooking purposes.

Why is hydrogen peroxide stored in dark bottles?

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You may have noticed that the hydrogen peroxide in your school laboratory is always stored in a dark tinted bottle. Ever wondered why? Check out this video of Hydrogen Peroxide. Continue reading.. What is hydrogen peroxide? Chemically known as H 2 O 2 , Hydrogen Peroxide is a chemical that has a variety of uses. Available as a pale blue liquid that is slightly more viscous than water, Hydrogen peroxide is a weak acid. Due to its strong oxidizing nature, hydrogen peroxide is often used as a bleaching agent. Peroxides are a class of chemical compounds where two oxygen atoms are linked with each other by a single covalent bond. The discovery of hydrogen peroxide Hydrogen peroxide was first discovered by Louis Jacques Thénard in 1818. This was achieved by reacting barium peroxide with nitric acid. Thénard’s process of creating hydrogen peroxide was widely used till the end of the 19th century. Making hydrogen peroxide Hydrogen Peroxide is produced naturally as

Chilly hot, water cold, chilly hot again?

When you've eaten something spicy, you take a quick gulp of water to damp the hotness. But after sometime, it feels hot again. Why? The hotness of chillies Chillies, bell peppers and other spicy ingredients in food cause its �hot�ness. This is because of a substance called capsaicin. The human tongue has many nerve endings called receptors that detect different tastes like sweet, bitter, sour and salty. One kind of receptors detects how warm the food is. Capsaicin irritates this receptor, causing the tongue to feel �hot�. The nature of capsaicin Capsaicin, like any other organic substance, has a complex structure. One end of it is made of a long, straight chain of carbon atoms. At the other end, there is a �benzene ring�, six carbon atom linked together in a circle. The two linked by an �amide bridge�. As carbon has a valency of four, there are different atoms attached to each carbon atom. ������� Benzene �ring�� �Amide bridge��������� �straight chain� �����

Chem Tutor

Hi chemo's how are you..? I'm here to announce the opening of chem tutor shortly on sunday .. Those who are interested they are all welcome ..they can join with me in the evenings.. There i am going to provide  the full pledged material which can be useful for all the competitive examinations in india ... I can promise you the best of the chemistry i will provide ... Expecting the cooperation from all my well wishers and all...