(a) Why is it necessary to balance a chemical equation ?
(b) Write the balanced chemical equations for the following reactions :
(i) Natural gas burns in air and combines with oxygen to form carbon dioxide and water.
(ii) During respiration, glucose combines with oxygen and forms carbon dioxide and water along with the release of energy.

Explanation

(a) For answer, consult Q.4 (N.C.E.R.T. End Exercise).
(b) `{:(CH_(4) + 2O_(2) to CO_(2) + 2H_(2)O),("(Natural Gas)"):}`
`{:(C_(6)H_(12)O_(6) + 6O_(2) to 6CO_(2) + 6H_(2)O + "energy"),("Glucose"):}`