Question

What is the pH of a buffer solution that contains 0.025 M HNO2

(Ka = 7.2 x 10-4) and 0.020 M NaNO2?


Select one:
A. 10.95
B. 3.05
C. 4.78
D. 9,22

Answer 1

Answer:

B.

Explanation:

H3O = 0.025×7.2×10-4/0.02

H3O = 0.0009M = 9×10-4

pH = -log[H+]

pH = -log[9×10-4]

pH = 3.05