Question

Write the equation for the acid dissociation, write the Ka expression, solve for Ht concentration, then do an ICE chart. Put the values into the Ka expression (the one you solved for Ht and find Ht, convert to pH and input that to 2 decimal place. Or use the Henderson-Hasselbalch equation:

pH = pka, + log ( Base/Acid)
Calculate the pH of a buffer solution consisting of 0.39 M HA (Ka = 8.8 x 10^-6) and 0.2 M NaA.

Answer 1

The pH of the buffer is 4.77

Step-by-step explanation:

Using Henderson-Hasselbalch equation we can solve the pH of the buffer:

pH = pKa + log [A⁻] / [HA]

Where pH is the pH of the buffer

pKa is -log Ka = 5.056

[A⁻] = [NaA] = 0.2M

[HA] = 0.39M

Replacing:

pH = 5.056+ log [0.2] / [0.39]

pH = 4.77

The pH of the buffer is 4.77