What is the concentration of hydroxide ions in a solution that has a pH of 6.0?

1 Answer
Mar 11, 2017

Answer:

#[HO^-]=10^-8*mol*L^-1#..........

Explanation:

We know that water undergoes self-ionization, which we may represent by the following reaction:

#H_2O rightleftharpoons H^+ + HO^-#

This equilibrium has been carefully measured, and at #298*K#, we may write,

#[H^+][HO^-]=10^-14#, and taking #log_10# of both sides,

#log_10[H_3O^+]+log_10[HO^-]=-14#

#-log_10[H_3O^+]-log_10[HO^-]=+14#

Given the definition of #pH=-log_10[H^+]#, then...........

#pH+pOH=14#

So if #pH=6#, then #pOH=8# and #[HO^-]=10^-8*mol*L^-1#.