Free Flowing Salts and Desiccants

Calcium silicate (CaSiO3), a commonly used anti-caking agent, added to e.g. table salt, absorbs both water and oil. This white powder has the incredible ability to absorb liquids and still remain a flee-flowing powder. In general, calcium silicate absorbs 1 ..

Ice Cubes are Cloudy on the Inside

Water contains both dissolved gases (e.g., oxygen) from the atmosphere and dissolved minerals (e.g., calcium and magnesium salts). The presence of these substances affects the temperature at which water freezes. Pure water freezes at 0~ water with dissolved gases and ..

Tarnishing of the Silver Jewellery and Utensils

Silver tarnish is the discoloration that occurs on silver. Silver is not appreciably affected by dry or moist air that is free from ozone, halogens, ammonia, and sulphur compounds. The presence of hydrogen sulphide in any material that silver comes ..

Colors in Fireworks

Pyrotechnics is the art of making fireworks, which produce different colours when lit. The art involves the intimate mixing of a fuel (burnable material) that is in a fine state of subdivision and an oxidising agent using a binder. This ..

Use of Chlorine in Swimming Pools

Chlorine, Iodine and Bromine can be used for disinfecting water but not fluorine because it is too reactive. Chlorine is often chosen simply because it is cheap, readily available and relatively easy to handle. Disinfection relies on disrupting a harmful ..

Knocking of Engines

An Internal combustion engine under load develops `pinging’ or `knocking’, where the fuel mixture starts exploding due to compression before the right time, causing rough running, stalling going up hills, and so on. Tetra Ethyl Lead (TEL) is one such ..

Barium- and Iodine-based materials are used as contrast media in X-Ray scans. Why?

The production of X-ray images depends on the differences between the X-ray absorbing powers of various tissues. This difference in absorbing power is called contrast and is directly dependent on tissue density. To artificially enhance the ability of a soft ..

Zeolites

Zeolites are microporous, aluminosilicate minerals commonly used as commercial adsorbents. Zeolites are widely used in industry for water purification, as catalysts, for the preparation of advanced materials and in nuclear reprocessing. They are used to extract nitrogen from air to increase ..