high school general chemistry

Molecular hydrides are soft. They are generally, volatile in nature and have low melting and boiling points. They have low electrical conductivity. The electronegativity difference between hydrogen and the atom bonded to it, determines the properties of covalent hydrides. When ..

In this process, coal is heated in the absence of air to about 1273 - 1473 K. The major products of high temperature pyrolysis are, Coal..

Ionic compounds are generally soluble in water and other polar solvents having high dielectric constants. This is due to larger electrostatic interactions between polar solvents and ions. However ionic compounds are insoluble in non-polar solvent..

Silicones are polymeric compounds containing Si-O-Si linkages. These have the general formula (R 2 SiO) n . These may be linear cyclic or cross-linked. These have very high thermal stability and are called high temperature polymers (R may be alkyl or phenyl group..

As a lubricant at higher temperatures. As a refractory material of making crucibles and electrodes for high temperature work. In electrotyping and in the manufacture of gramophone records: Graphite is used for making the non-conducting (generally wax) surface, so that el..

The general formula of Haloalkane (CnH 2 n + 1 - X) or Haloarene is 'RX' where R - is an alkyl or aryl group and X is a halogen atom (F, Cl, Br or I). The halogen derived hydrocarbons are a highly reactive class of compounds. The reactivity is due to the presence of po..

The heat changes in chemical reactions are measured with the help of calorimeters. Depending upon the requirements of experiments different types of calorimeters are used. In general, reactions taking place at constant volume and involving gases are carried out in a closed container..

'd' block elements have valence electrons in both their outermost and penultimate shells. Valence electrons belonging to the outermost shell or both shells may take part in a chemical reaction. Accordingly, more than one oxidation state can be shown by the same element; this is termed as variable..

Physisorption Chemisorption Forces of attraction are vander Waals’ forces Forces of attraction are chemical bond forces Low enthalpy of adsorption (20 - 40 k.J/mole) High enthapy of adsorption (200 - 400 k.J/mole) This process is observed under conditions o..

Amides - Preparation - Amides are generally prepared by the reaction of acyl chlorides or anhydrides with ammonia or amine..