Three solutions have the following pH values:

Solution A: pH = 11
Solution B: pH = 10.4
Solution C: pH = 8.2

Which solution has the smallest Kb?

a) A
b) B
c) C
d) Impossible to determine

Question

Three solutions have the following pH values:

Solution A: pH = 11 
Solution B: pH = 10.4
Solution C: pH = 8.2

Which solution has the smallest Kb?

a) A
b) B
c) C
d) Impossible to determine

anonymous · Answer

With the given pH values of the 3 solutions, one can determine the pOH, and in turn, find the Kb value only with the known concentration of the conjugate Acid/Base. We do not have those values, so there is no way for us to find the Kb, making our answer to the problem d) Impossible to Determine.

Things we can find with the information given:
~pOH
~[OH-]

Things we cannot find:
~Kb
~Ka