Question

Calculate the grams or milliliters of solute needed to prepare the following:

a.$\text{50}\mathrm{g}\text{of a}5.0\%(\mathrm{m}/\mathrm{m})\mathrm{KCl}$solution.

b. $1250\mathrm{mL}\text{of a}4.0\%(\mathrm{m}/\mathrm{v}){\mathrm{NH}}_4\mathrm{Cl}$solution.

c. $\text{250}\mathrm{mL}\text{of a}10.0\%(\mathrm{v}/\mathrm{v})$acetic acid solution.

Short answer

(part a) Weight of the $\text{50}\mathrm{g}\text{of a}5.0\%(\mathrm{m}/\mathrm{m})\mathrm{KCl}$solution is $60g.$

(part b) Weight of the $1250\mathrm{mL}\text{of a}4.0\%(\mathrm{m}/\mathrm{v}){\mathrm{NH}}_4\mathrm{Cl}$solution is $6g.$

(part c) Volume of the $250\mathrm{mL}\text{of a}10.0\%(\mathrm{v}/\mathrm{v})$acetic acid solution is $33.75mL$

Step-by-step solution

Given Information (part a).

The following information are used to find the mass or milliliters of solute:

$\text{50}\mathrm{g}\text{of a}5.0\%(\mathrm{m}/\mathrm{m})\mathrm{KCl}$solution.

To find the Weight's value (part a).

By using the following equation, find the mass percentage,

$\text{Mass percent}(\mathrm{m}/\mathrm{m})=\frac{\text{Solute mass}}{\text{Solution mass}}\times 100\mathrm{\%}$

Substitute the values by rearranging the equation ,

$$\begin{gathered} \text{Solute mass}=\frac{\text{Mass percent}(\mathrm{m}/\mathrm{m})\times \text{Solution mass}}{100\mathrm{\%}} \\ =\frac{40.0\mathrm{\%}\times 150\mathrm{g}}{100\mathrm{\%}} \\ =60g \end{gathered}$$

Given Information (part b).

The following information are used to find the mass or milliliters of solute:

$1250\mathrm{mL}\text{of a}4.0\%(\mathrm{m}/\mathrm{v}){\mathrm{NH}}_4\mathrm{Cl}$solution.

Explained the weight value (part b).

Find the mass using the equation,

$\text{Mass percent}(\mathrm{m}/\mathrm{m})=\frac{\text{Solute mass}}{\text{Solution mass}}\times 100\mathrm{\%}$

Substitute the values by rearranging the equation ,

$$\begin{gathered} \text{Solute mass}=\frac{\text{Mass percent}(\mathrm{m}/\mathrm{m})\times \text{Solution mass}}{100\mathrm{\%}} \\ =\frac{2.0\mathrm{\%}\times 450\mathrm{mL}}{100\mathrm{\%}} \\ =6g \end{gathered}$$

Given Information (part c).

The following information are used to find the mass or milliliters of solute:

$\text{250}\mathrm{mL}\text{of a}10.0\%(\mathrm{v}/\mathrm{v})$acetic acid solution.

Explained the Weight (part c).

The mass equation is as follows:

$\text{Volumepercent}(\mathrm{m}/\mathrm{m})=\frac{\text{Volumemass}}{\text{Volumemass}}\times 100\mathrm{\%}$

Rearrange the equation to substitute the value,

$$\begin{gathered} \text{Solute volume}=\frac{\text{Volume percent}(\mathrm{m}/\mathrm{m})\times \text{Solution volume}}{100\mathrm{\%}} \\ =\frac{15.0\mathrm{\%}\times 225\mathrm{mL}}{100\mathrm{\%}} \\ =33.75\mathrm{mL} \end{gathered}$$