Question

When I compare a 1.00 M solution of LiOH(aq) to a 1.00 M solution of sodium hypochlorite bleach, NaCLO(aq), kb=2.86(10^-7)?.....(Multiple choice)

a. The LiOH solution is exactly as basic as the bleach

b. the bleach solution is 15.1 times more basic than the LiOH

c. the LiOH solution is 334 times more basic than the bleach

d. the LiOH solution is 1870 times more basic than the bleach

e. the bleach solution is 3.50(10^6) more basic than the

Please explain why. thanks.

Answer 1

Correct option is (d.) the LiOH solution is 1870 times more basic than the bleach

Explanation

LiOH is a very strong base which completely dissociates in aqueous solution.

Hence [OH^-] = [LiOH] = 1.00 M

But NaClO is weak base which undergoes hydrolysis reaction

For NaClO, [OH^-] = 5.346 x 10^-4 M     (see pic for calculations)

[OH^-]_LiOH / [OH^-]_NaClO = 1.00 M / 5.346 x 10^-4 M

[OH^-]_LiOH / [OH^-]_NaClO = 1870

[OH^-]_LiOH = 1870 * [OH^-]_NaClO

This proves LiOH solution is 1870 times more basic than the bleach