Question

Another way to express acid strength is by using pKa:

pK a=%u2212logKa
Another way to express base strength is by using pKb:
pKb=%u2212logKb


PART A:
A new potential heart medicine, code-named X-281, is being testedby a pharmaceutical company, Pharma-pill. As a research technicianat Pharma-pill, you are told that X-281 is a monoprotic weak acid,but because of security concerns, the actual chemical formula mustremain top secret. The company is interested in the drug's Ka valuebecause only the dissociated form of the chemical is active inpreventing cholesterol buildup in arteries.
To find the pKa of X-281, you prepare a 0.081M test solution ofX-281. The pH of the solution is determined to be 3.00. What is thepKa of X-281?

***I ALREADY FOUND THE ANSWER TO THIS PART (4.90), BUT I NEED PARTB!!
PART B:
For any conjugate acid-base pair
pKa+pKb=14.00

What is pKb of the conjugate base of X-281?
Express your answer numerically.

ANSWER:
pKb=_____________???

***NOTE: DO NOT COPY AND PASTE OFF OF YAHOO ANSWERS (THE ANSWER ISNOT 4.34 OR 9.66) OR ANOTHER PROBLEM PLEASE. YOU'LL BE WASTING NOTONLY YOUR TIME BUT MINE. I'D REALLY APPRECIATE HELP!THANKS!!!***

PART C:
Unlike strong acids and bases that ionize completely in solution,weak acids or bases partially ionize. The tendency to ionize (i.e.,the ionic strength) of a weak acid or base can be quantified inseveral ways including
Ka or Kb,
pKa or pKb,
and percent ionization.

Benzoic acid is a weak acid that has antimicrobial properties. Itssodium salt, sodium benzoate, is a preservative found in foods,medications, and personal hygiene products. Benzoic aciddissociates in water:
C6H5COOH <=> C6H5COO^- + H^+
The ppKa of this reaction is 4.2. In a 0.60 M M
solution of benzoic acid, what percentage of the molecules areionized?
Express the percentage numerically using two significantfigures.
ANSWER:
percentionized=_____________%???