The dissociation constant of a weak acid is 1 × 10^ -4 . In order...

$\mathrm{pH}=\mathrm{pK}_a+\log \frac{[\text{ Salt }]}{\text{ Acid }}$ \begin{aligned} & 5=\log \left[1 \times 10^{-4}\right]+\log \frac{[\text{ Salt }]}{[\text{ Acid }]} \\ & 5=4+\log \frac{[\text{ Salt }]}{[\text{ Acid }]} \\ & \frac{[\text{ Salt }]}{[\text{ Acid }]}=10: 1 \end{aligned}