A sample of the diprotic acid has and

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

Problem

A sample of the diprotic acid

H_2A

has

pK_{a1}=2.0

and

pK_{a2}=6.5

. Analysis shows that the singly deprotonated species

HA^-

is overwhelmingly predominant. Which pH range is most consistent with this observation? (a) pH

\approx

2.0 (b)

2.0 < \text{pH} < 6.5