Is #NH_3# a weak or strong base? Chemistry Acids and Bases Acids and Bases 1 Answer anor277 Jun 28, 2016 In aqueous solution, ammonia, #NH_3# acts as a weak base. Explanation: #NH_3(aq) + H_2O(l) rightleftharpoons NH_4^+ + HO^-# #pK_b# #=# #4.75# Answer link Related questions How do resonance structures affect acidity? How does carbon dioxide change the acid-base condition of a solution? Why do strong acids have a low pH? Is neutralization a double replacement reaction? Why is NaH a strong base? Is HBr a strong acid? Is HF a strong acid? Why does neutralization occur? Do strong acids completely dissociate in water? How can I calculate pH of weak acid? See all questions in Acids and Bases Impact of this question 1983 views around the world You can reuse this answer Creative Commons License