CH 2 CHEMICAL CHANGE AND REACTIONS

It is a reaction that occurs with absorption of electrical energy .

It is a reaction that occurs with absorption of light energy.

Substances such as methane, which undergo combustion readly and give out a large amount of energy are known as fuels.

The reaction in which heat is absorbed. ,that reaction is called endothermic reaction. e.g. CaCO3 (s) + Heat ⟶ CaO(s)+CO2 (g)

The reaction in which heat is evolved .

The reaction between an acid and a base that forms salt and water only is referred to as a reaction of neutralization.

A chemical reaction in which two copounds in their aqueous state react to form an insoluble salt as one of the products is known as Precipitation reaction.

This is a type of chemical change in which two compounds in a solutions react to form two new compounds by mutual exchange of radicals .

It is a chemical change in which a more active element displaces a less active element from its salt solution .

a reversible decomposition reaction brought about only by it is called thermal dissociation .