Question

Write the Ka reaction for formic acid, HCO2H, and for methylammonium ion, CH3NH+
3 . How do I approach this?

Answer 1

The question isn't clear to me but I assume you are looking for TWO separate Ka reactions.
HCO2H + H2O ==> H3O^+ + HCO2^-
Ka = (H3O^+)(HCO2^-)/HCO2H) = ?

CH3NH3^+ + H2O ==> H3O^+ + CH3NH2

Ka for CH3NH2^+ = (Kw/Kb for CH3NH2) = (H3O^+)(CH3NH2)/(CH3NH3^+)

Answer 2

Thank you Dr. Bob! :)I had that but it seemed too simple to be true. I didn't have my text to verify.