0.10 M solution of a weak monoprotic acid has a hydronium-ion concentration of 5.0 * 10^-4 M. What is the equilibrium constant, Ka, for this acid?

a. 5.0 *10^-2

b. 5.0 * 10^-3

c. 2.5 * 10^-4

d. 2.5 * 10^-5

e. 2.5 * 10^-6

2. (Points: 1)
What is the carbonate-ion, CO3^-2, concentration in a 0.037 M carbonic acid solution?

a. 1.2 ´ 10^-4

b. 4.2 ´ 10^-7

c. 7.6 ´ 10^-8

d. 4.8 ´ 10^-11

e. 5.2 ´ 10^-19

1 answer

1. c
2. a