[xstrae]

Hi,

1. Which of the following form conjugate acid - base pairs in the right order?
(A) NaCl + NaOH
(B) Borax + Boric Acid
(C) NaH₂PO₄
(D) NH₄Cl + NH₄OH

Solution : B and D

2. Which of the following form conjugate acid-base pairs in the right order?
(A) NH₃, NH₂
(B) OH^-, H₂O
(C) HCO₃^-, CO₂^-
(D) H₂S , HS^-

Solution: B and D

Please help me out with the above 2 problems.  I always thought that a conjugate acid-base differ by a H, but the answers indicate otherwise.

[AWK]

You are right concernig definition. Try use it
eg
1D NH₄⁺ and NH₃

[xstrae]

Allright, I understand now. thanks! it just clicked now

but one doubt, is B correct for the second question? isnt OH^- the conjugate base of H2O? I mean, they are a conjugate acid - base pair, but in the opposite order.