Chapter U4.82, Problem 1E

Interpretation Introduction

Interpretation:

The preparation of a solution of sucrose with a molarity of 0.25 needs to be explained.

Concept introduction:

Molarity of a solution is the moles of solute per 1 L solution.

Answer to Problem 1E

85.5 g sucrose must be dissolved in 1L solution.

Explanation of Solution

Required molarity of the sucrose solution is 0.25 M

This means 0.25 mol of sucrose is dissolved in 1 L of the solution.

Molar mass of sucrose is 342 g/mol

Mass of sucrose will be:

  $\begin{array}{l}m=n\times M\\ m=\text{0}\text{.25 mol×342 g/mol}\\ \text{=85}\text{.5 g}\end{array}$

Thus, the mass of sucrose required is 85.5 g.

Conclusion

One would prepare a solution of sucrose with a molarity of 0.25 by dissolving 85.5 g sucrose in 1L solution.