# Question 3470c

Apr 9, 2017

$\text{34 g TSP}$

#### Explanation:

A solution's mass by volume percent concentration, $\text{% m/v}$, tells you the number of grams of solute present for every $\text{100 mL}$ of solution.

In your case, a $\text{1.7% m/v}$ trisodium phosphate solution will contain $\text{1.7 g}$ of trisodium phosphate, the solute, for every $\text{100 mL}$ of solution.

You know that the solution has a total volume of

2 color(red)(cancel(color(black)("L"))) * (10^3color(white)(.)"mL")/(1color(red)(cancel(color(black)("L")))) = 2 * 10^3# $\text{mL}$

which means that it must contain

$2 \cdot {10}^{3} \textcolor{red}{\cancel{\textcolor{b l a c k}{\text{mL solution"))) * overbrace("1.7 g TSP"/(100color(red)(cancel(color(black)("mL solution")))))^(color(blue)("= 1.7% m/v TSP solution")) = color(darkgreen)(ul(color(black)("34 g TSP}}}}$

in order to have the desired mass by volume percent concentration.

The answer is rounded to two sig figs.

Remember, you can use the known percent concentration of a solution as a conversion factor because solutions are homogeneous mixtures, which means that they have the same composition throughout.