How do you calculate a Ka value from pKa?

1 Answer
Feb 2, 2016

#pK_a# #=# #-log_10K_a#. Thus #K_a# #=# #10^(-pK_a)#

Explanation:

Remember your definitions for logarithmic functions. When we write #log_ab = c#, we specify that #a^c =b#. For example #log_(10)100 = 2#, and #log_(10)1000 = 3#. It follows that exceptionally strong acids have NEGATIVE #pK_a"'s"#.