Chapter U4.81, Problem 2E

Interpretation Introduction

Interpretation:

The way to calculate the number of moles of solute in a solution with given concentration needs to be explained.

Concept introduction:

Concentration of a solution is the amount of solute dissolved in particular volume of solutions.

Some of the concentration units of solution are g/L, molarity (M), molality (m), mole fraction, etc. Molarity is the number of moles of solute dissolved in 1 L solution whereas molality is the number of moles of solute in 1 kg of solvent.

Answer to Problem 2E

Moles of solute can be found from the following formula.

  $n=M\times V$

Here, M is molarity and V is volume of the solution in L.

Explanation of Solution

This can be explained by taking an exampole of 5 M glucose solution. Let the number of moles of glucose needs to be found in 1500 mL of the solution.

Molarity of glucose solution is 5 means 1 L (1000 mL) solution contains 5moles of glucose.

So 1500 mL or 1.5 L solution contains $\text{5}\times \text{1}\text{.5=7}\text{.5 moles of glucose}$ .

Thus, from molarity and volume of the solution, moles of solute can be found out.

Conclusion

Moles of solute in a solution with specific concentration can be figured out using the concentration of the solution and the volume of the solution.