# Question #0ac55

Mar 18, 2017

$\text{1.4 L}$

#### Explanation:

For a given solution, we use molarity to express the number of moles of solute present for every $\text{1 L}$ of solution.

In this case, a $\text{2.8-M}$ solution must contain $2.8$ moles of solute for every $\text{1 L}$ of solution.

Now, solutions are homogeneous mixtures, which implies that they have the same composition throughout. Consequently, you can say that $4.00$ moles of solute in an unknown volume of solution must be equivalent to $2.8$ moles of solute in $\text{1 L}$ of solution.

In other words, you can use the molarity of the solution as a conversion factor to determine the volume of the solution that must contain $4.00$ moles in order to have a solution that would contain $2.8$ moles of solute in $\text{1 L}$ of solution

$4.00 \textcolor{red}{\cancel{\textcolor{b l a c k}{\text{moles solute"))) * "1 L solution"/(2.8color(red)(cancel(color(black)("moles solute")))) = color(darkgreen)(ul(color(black)("1.4 L solution}}}}$

The answer is rounded to two sig figs, the number of sig figs you have for the molarity of the solution.