How would you write the ionization equation for benzoic acid (C6H5COOH)? Chemistry The Periodic Table Periodic Trends in Ionization Energy 1 Answer anor277 Dec 31, 2015 #C_6H_5CO_2H(aq) + H_2O(l) rightleftharpoons C_6H_5CO_2^(-) + H_3O^+# Explanation: #K_a# #=# #[[C_6H_5CO_2^-][H_3O^+]]/[[C_6H_5CO_2H(aq)]]# The #pK_a# of benzoic acid is #4.2#, whereas the #pK_a# of acetic acid is #4.7#. Can you account for why acetic acid is a weaker acid than benzoic acid? Note #pK_a = -log_(10)K_a#. Answer link Related questions How does ionization energy relate to reactivity? What is ionization energy measured in? What are the first and second ionization energies? How does ionization energy increase? How does ionization energy change down a group? How do trends in atomic radius relate to ionization energy? Question #44238 Question #fbdfe Question #1a23b Question #d7de9 See all questions in Periodic Trends in Ionization Energy Impact of this question 12446 views around the world You can reuse this answer Creative Commons License