Question

A buffer solution is made using a weak acid, HA , that has a pKa of 5 . If the pH of the buffer is 7 , what is the ratio of [A−] to [HA] ? [A−][HA]=

Answer 1

The ratio of [A−] to [HA] in the buffer is 100.

Step-by-step explanation:

A buffer solution is made using a weak acid, HA, that has a pKa of 5. If the pH of the buffer is 7, the ratio of [A−] to [HA] can be determined using the Henderson-Hasselbalch equation:

pH = pKa + log([A¯]/[HA])

Now, let's calculate the ratio:

7 = 5 + log([A¯]/[HA])
log([A¯]/[HA]) = 2
[A¯]/[HA] = 10^2
[A¯]/[HA] = 100