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Group VIIA elements: F, Cl, Br, I

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pH

Negative logarithm of the concentration (mol/L) of the H3O+[H+] ion, scale is commonly used over a range 0 to 14.

Strong Field Ligand

Ligand that exerts a strong crystal or ligand electrical field and generally forms low spin complexes with metal ions when possible.

Differential Thermal Analysis (DTA)

A technique for observing the temperature, direction, and magnitude of thermally induced transitions in a material by heating/cooling a sample and comparing its temperature with that of an inert reference material under similar conditions.

Aryl Group

Group of atoms remaining after a hydrogen atom is removed from the aromatic system.

Hydrogen

Discovered : by Henry Cavendish in 1766.
Isolated in London, UK.
Origin : The name is derived from the Greek ‘hydro genes’, meaning water forming.
Description :A colourless, odourless gas that burns and can form an explosive mixture with air. It is currently manufactured from methane gas, but is also produced by the electrolysis of water and aqueous salts. The gas is used to make such key materials as ammonia, cyclohexane and methanol, which are intermediates in the production of fertilisers, plastics and pharmaceuticals. Some see hydrogen gas as the clean fuel of the future - generated from water and returning to water when it is oxidised. Hydrogen-powered fuel cells are increasingly being seen as pollution-free sources of energy.

Atomic Radius

Radius of an atom.

Cyclotron

A device for accelerating charged particles along a spiral path.

Bubbles

Have you ever noticed that soap bubbles go up in winter and fall down in summer? The reason is that warm air is lighter than cold. And in winter the difference between the air temperature in the room (especially near the windows) and the one you exhale into the bubble is enough to overcome the heaviness of its shell.

Salt and its use in everyday life

Cooking salt is a product that is available in every kitchen, and it’s not as simple as it seems. The history of this product shows that it was valued like gold.

xylan

The pentosan occurring in woody tissue that hydrolyzes to xylose: used as a source of furfural.