Weak acids don't ionize completely.
HCOOH ==> H^+ + HCOO^- for which
Ka = (H^+)(HCOO^-)/(HCOOH)
There are no unit for Ka. If you use molarity for concn, as most do, there appears to be "formal" units but in higher chemistry courses you will learn there are no units since the numbers that go in are activities and they have no units.
(a) Explain what is meant by a weak acid.
Methanoic acid (HCO2H) has a numerical value of Ka(T) at 298K of 1.60 × 10-4
(b) Write an expression for Ka(T) of methanoic acid, and state its units.
(c) What is the pH value of a 0.10 mol dm-3 aqueous solution of methanoic acid? Give a clear account of your calculation and state any assumptions you have made
2 answers
What is the pH value of a 0.10 mol dm-3 aqueous solution of methanoic acid? Give a clear account of your calculation and state any assumptions you have made
1 answer