Indicator X has

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

Problem

Indicator X has

pK_a = 6.4

. The protonated form of the indicator is orange, and the deprotonated form is purple. What is the approximate ratio

[\text{acid form}]:[\text{base form}]

pH = 5.4

? (a)

1:10

(b)

100:1

(c)

10:1

(d)

1:1