Question

Calculate the mass of sodium acetate that must be added to 500.0 mL of 0.200 M acetic acid to form a pH 5 5.00 buffered solution.

Short answer

The mass of sodium acetate required to prepare the buffer of $\text{pH}=5.0$is around$15 \text{g}$.

Step-by-step solution

Definition of mass

The quantity of matter inside a body is determined by its mass.

Calculation of mass of sodium acetate

The molarity of the solution is$0.360 \text{moles/L}$.

Moles of sodium acetateare$0.180 \text{moles}$ .

The mass of sodium acetate is calculated as follows:

$$\begin{gathered} \text{Mass} \text{of} {\text{CH}}_{\text{3}}\text{COONa}=\text{Moles} \text{of} {\text{CH}}_{\text{3}}\text{COONa}\times \text{Mol.weight} \\ =0.180 \text{moles}\times 82 \text{g/mol} \\ \text{= 14.76} \\ \simeq \text{15.0} \text{g} \end{gathered}$$