Question

Calculate the mass/volume percent $(m/v)$for the solute in each of the following:

a. $2.50\mathrm{g}\text{of}\mathrm{LiCl}$in $40mLof\mathrm{LiCl}$solution.

b. $7.5\mathrm{g}$of casein in $20mL$of low-fat milk.

Short answer

(part a) The mass/volume percent for the solute 2.50 g in $\text{40mLof}\mathrm{LiCl}$solution is$6.25\%(m/v).$

(part b) The mass/volume percent for the solute$7.5\mathrm{g}$of casein in$20mL$of low-fat milk is$6.25\%(m/v).$

Step-by-step solution

Given Information (part a)

The following are the given information to find mass/volume percent:

$2.50\mathrm{g}\text{of}\mathrm{LiCl}$in$\text{40mLof}\mathrm{LiCl}$solution.

Find the mass/volume percent (part a).

The equation for mass volume percent is,

$\text{Mass}/\text{volume percent}(\mathrm{m}/\mathrm{v})=\frac{\text{Mass of solute}}{\text{Volume of solution}}\times 100$

Substitute the values in equation,

$$\begin{gathered} =\frac{2.50\mathrm{g}}{40.0\mathrm{mL}}\times 100 \\ =6.25\%(m/v)LiCl \end{gathered}$$

Given Information (part b).

The following are the given information to find mass/volume percent:

$7.5g$of casein in$20mL$of low-fat milk.

Find the mass/volume percent (part b). 

The equation for mass volume percent is,

$\text{Mass}/\text{volume percent}(\mathrm{m}/\mathrm{v})=\frac{\text{Mass of solute}}{\text{Volume of solution}}\times 100$

Substitute the values in equation,

localid="1653894531372" $$\begin{gathered} =\frac{7.5\mathrm{g}\text{casein}}{120\mathrm{mL}\text{milk}}\times 100\mathrm{\%} \\ =6.25\%(\mathrm{m}/\mathrm{v}) \end{gathered}$$