(a)What happens when calcium reacts with water? Write the chemical equations of the reaction of calcium with water.
(b)Write the chemical equation of the reaction which takes place when iron reacts with dilute sulphuric acid. What happens when the gas produced is ignited with a burning matchstick?

(a) Calcium reacts with cold water to form calcium hydroxide and hydrogen gas.

$Ca + 2H_2O → Ca(OH)_2 + H_2$

(b) When irons react with dilute sulphuric acid to forms iron sulphate and hydrogen gas.

$Fe + H_2SO_4 → FeSO_4 + H_2$

When hydrogen gas is ignited with a burning matchstick, it produces a ' pop' sound.