Q9 of 39 Page 1

(a) What is meant by balanced chemical equation? Why chemical equations are balanced?

(b) Balance the chemical equation given below:


Al2O3 + NaOH → NaAlO2 + H2O (2013)


(a) A balanced chemical equation has an equal number of atoms of different elements in the reactants and products. It means a balanced chemical equation has equal masses of various elements in reactants and products.

According to law of conservation of mass, “Matter can neither be created nor destroyed in a chemical reaction”. Therefore the chemical equations are balanced to satisfy the law of conservation of mass in chemical reaction.


(b) Al2O3 + 2NaOH 2NaAlO2 + H2O


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