# What is the mol fraction of water in an aqueous solution of #"3 M NaOH"#?

##### 1 Answer

May 4, 2017

Assuming

We approximate that the density of the solution is that of water, and assume a

#"1 L soln" xx "997.0749 g water"/"1 L soln" xx "1 mol water"/"18.015 g" ~~ "55.35 mols water"#

From this we can tell that this is dilute enough for the above approximation. Proceeding, we can then get the mol fraction. To illustrate a point, let us first find the mol fraction of solute:

#chi_(NaOH) = "3 mols NaOH"/("3 mols NaOH" + "55.35 mols water")#

#= 0.0514#

Therefore, the **mol fraction of water** is approximately