How do you find pOH given pH?

1 Answer
May 9, 2016

#pOH=14-pH#

Explanation:

To find the #pOH# from the given #pH# you can simply use the following relationship:

#pOH=14-pH#

This relationship is derived from the expression of the water dissociation constant #K_w#, where,

#K_w=[H^(+)][OH^(-)]=1.0xx10^(-14)#

Taking the #-log# of both parties we get:

#-logK_w=-log[H^(+)]-log[OH^(-)]=14#

Therefore, #pH+pOH=14=>pOH=14-pH#

remember, #pH=-log[H^(+)]# and #pOH=-log[OH^(-)]#

This is a video that talks more about this topic:
Acids & Bases | Nature, Strength & pH Scale.