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When a question gives a compound and its Kb, and wants to know which of the following has a Ka of (insert number). Do I simply look for the conjugate acid?
example: NH3 has a Kb of 1.8*10^-5. Which of the following has a Ka of 5.6 *10^-10?
The answer is NH4+, which is the conjugate acid for NH3.
One last question. If they give me the pKa for some acid in the passage and the question is asking for the pKb of this compound's conjugate base, do I simply take the pKa and subtract it from 14?
example: H2SO3 has a pKa of 1.81
What is the pKb for HSO3-?
Answer is 12.19 (14 - 1.81)
example: NH3 has a Kb of 1.8*10^-5. Which of the following has a Ka of 5.6 *10^-10?
The answer is NH4+, which is the conjugate acid for NH3.
One last question. If they give me the pKa for some acid in the passage and the question is asking for the pKb of this compound's conjugate base, do I simply take the pKa and subtract it from 14?
example: H2SO3 has a pKa of 1.81
What is the pKb for HSO3-?
Answer is 12.19 (14 - 1.81)
