Question

which are conjugate acid/base pair? which one or both?

a.) NH4+/NH3

b.) H3O+/OH-

Answer 1

The conjugate acid base pair is one which may be converted to each other by exchange of a proton

The conjugate acid is one which will lose a proton to give its conjugate base and vice versa

a) NH4+/NH3

NH₄⁺ --> NH₃ + H⁺

Acid       conjugate base

b) H₃O⁺ ---> H₂O + H⁺

so the conjugate base of H3O+ will be H2O (not OH-)

OH- is conjugate base of H2O

H2O --> OH- + H⁺

a.) NH4+/NH3 (conjugate acid base pair)

b.) H3O+/OH- (not)