A buffer is prepared by mixing of 0.20 M HA with of 0.20 M NaA

CHEMISTRY · Single correct · A Level · Chemistry · Acids and bases · Acids and bases

Problem

A buffer is prepared by mixing

50.0\,\text{mL}

of 0.20 M HA with

35.0\,\text{mL}

of 0.20 M NaA. The measured pH of the resulting solution is 3.65. What is the

pK_a

of HA? (a)

3.50

(b)

4.01

(c)

3.81

(d)

3.65