Chapter 3, Problem 52A

Interpretation Introduction

Interpretation:

For the given reaction, mass of chlorine gas used needs to be determined.

Concept introduction:

According to law of conservation of mass, total mass of reactant and product in a chemical reaction remains the same before and after the completion of the reaction.

Answer to Problem 52A

70.91 g.

Explanation of Solution

The mass of sodium is 45.98 g. It reacts with excess of chlorine gas to form 116.89 g of sodium chloride.

In the given reaction, reactants are sodium and chlorine gas and product is sodium chloride. According to the law of conservation of mass, the total mass of reactants will be equal to the total mass of products after the reaction or no mass is lost during the reaction.

This can be represented as follows:

$m_{\text{sodium}}+m_{\text{chlorine gas}}=m_{\text{sodium chloride}}$

Putting the values,

$\begin{array}{l}45.98+m_{\text{chlorine gas}}=116.89\\ m_{\text{chlorine gas}}=\left(116.89-45.98\right)\text{ g}=70.91\text{ g}\end{array}$

Conclusion

Thus, the mass of chlorine gas used is 70.91 g.