Chapter U4.82, Problem 2E

Interpretation Introduction

Interpretation:

The relation between mass of solute, moles of solute and volume of solution needs to be explained.

Concept introduction:

Molarity of a solution is the moles of solute per 1 L solution. Moles of a solute is ratio of mass and molar mass of the solute.

Answer to Problem 2E

The relation between mass of solute, number of moles of solute and volume of solution is as follows:

  $m=M\times V\times \text{Molar mass}$

Here, m is mass of solute, M is molarity and V is volume of solution in L.

Explanation of Solution

Molarity is number of moles of solute in 1 L of the solution.

  $M=\frac{n}{V\left(L\right)}$

Here, n is number of moles of solute and V is volume of solution.

The number of moles is related to mass and molar mass as follows:

  $n=\frac{m}{\text{Molar mass}}$

Thus,

  $M=\frac{\frac{m}{\text{Molar mass}}}{V\left(L\right)}=\frac{m}{V\left(L\right)\times \text{Molar mass}}$

Also,

  $m=M\times V\times \text{Molar mass}$

Here, m is mass of solute, M is molarity and V is volume of solution in L.