Question

The mole fraction of NaCl in anaqueous solution is 0.132. Howmany moles of NaCl are present in1 mole of this solution?Molar MassNaCl: 58.44 g/molH2O: 18.016 g/mol

Answer 1

The mole fraction of a solution is the number of moles of NaCl, the solute, divided by the total number of moles of solution:

$f=\frac{n_{NaCl}}{n_{\text{solution}}}$

If we have 1 mol of solution, then:

$n_{\text{solution}}=1mol$

And the mole fraction is given, so:

$f=0.132$

So, to calculate the number of moles of NaCl, we can solve for it and input the given values:

$\begin{gathered} f=\frac{n_{NaCl}}{n_{\text{solution}}} \\ n_{NaCl}=f\cdot n_{\text{solution}} \\ n_{NaCl}=0.132\cdot1mol \\ n_{NaCl}=0.132mol \end{gathered}$

So, there are 0.132 moles of NaCl in the solution.