Chapter 16, Problem 43A

Interpretation Introduction

Interpretation:

Volume of given sodium hydroxide solution is to be calculated when it is neutralized by acid.

Concept introduction:

Molarity is number of moles of solute present per liter of solution.

When acid and base are mixed, they neutralize each other. So their molar concentrations can be calculated by applying mole concept.

Answer to Problem 43A

Volume of sodium hydroxide is $1.5L$

Explanation of Solution

Given Information$\begin{array}{l}{V}_{HCl}=1L\\ MolarityofHCl=3\text{}M\\ MolarityofNaOH=2\text{}M\end{array}$

Calculation:

  $\begin{array}{c}{n}_{HCl}=Molarity\times volumeinliters\\ =3\times 1\\ =3mol\end{array}$

When hydrochloric acid reacts with sodium hydroxide reaction is given by:

  $HCl+NaOH\to NaCl+H_{2}O$

Thus one mol acid reacts with one mol base.

This impies,

  $n_{NaOH}=3mol$

  $\begin{array}{c}VolumeofNaOHsolution=\frac{3mol}{2M}\\ =1.5L\end{array}$

Conclusion

  $VolumeofNaOH=1.5L$