a) What is chemical decomposition reaction?
b) In what conditions chemical decomposition reactions takes place ? Explain various condition.

Explanation

Chemical decomposition reaction : A chemical reaction in which a single substance splits into two or more substances is called chemical decomposition.
Decomposition reaction can be takes place in varies conditions. Those are
a) On heating : If the chemical reaction takes place when heat energy is supplied it is called thermal decomposition reaction
Or
A decomposition reaction is carried out by heating is called thermal decomposition reaction.
Eg : `CaCO_(3) overset("heat")rarr CaO+CO_(2)`
b) In the presence sunlight : A decomposition reaction occurs in the presence of sunlight, is called photochemical reaction.
Eg : `2AgBr overset("sunlight")rarr 2Ag+Br_(2)`
c) By supplying electricity : The decomposition reaction takes place in electrolysis method is called decomposition reaction by electrolysis.
Eg : Water dissociates to hydrogen and oxygen.
`2H_(2)O overset("electrolysis")rarr 2H_(2)+O_(2)`