State three applications of a decomposition reaction. 

With the help of an activity, show that the reaction between calcium oxide (lime) and water is an exothermic reaction. 

When a metal rod is immersed in an aqueous copper sulphate solution, the blue colour of the solution changes to pale green. What is the metal with which the rod is made up of? 

Explain two effects of oxidation reactions in everyday life. 

Write balanced chemical equations for the following word equation: 

Calcium hydroxide $+$ Carbon dioxide $\to$ Calcium carbonate $+$ Water.