Chapter 7, Problem 31A

Interpretation Introduction

Interpretation :

The factor which is counted on both the side of an equation to check that an equation is balanced must be explained.

Concept Introduction :

A balanced chemical equation represents a chemical reaction in which number of atoms is same on both the side of the equation.

Answer to Problem 31A

Number of atoms is counted to check that an equation is balanced.

Explanation of Solution

  ${\text{NaCl(aq)+AgNO}}_{\text{3}}\text{(aq)}\to \text{AgCl(s)}\downarrow {\text{+NaNO}}_{\text{3}}\text{(aq)}\text{.}$

From the above chemical equation it is clear that number of each atom are same on both the sides of the equation. Numbers of Na, Cl, Ag, N and O in both the sides are 1,1,1,1 and 3 respectively. This is the requirement of law of conservation of mass.

Conclusion

Number of atoms is counted in both the side of an equation to check that a reaction is balanced.