Question #f0437

1 Answer
Apr 29, 2015

In one word: yes.

If you know the concentration of the hydroxide ions, you can determine the solution's pOH by

#pOH = -log([OH^(-)])#

#pOH = -log(1.9 * 10^(-6)) = 5.72#

This will indirectly get you the pH of the solution

#pH_"sol" = 14 - pOH = 14 - 5.72 = 8.28#

Now use the pH to determine the concentration of the hydronium ions

#[H_3O^(+)] = 10^(-pH_"sol") = 10^(-8.28) = 5.3 * 10^(-9)"M"#

Alternatively, you can calculate the concentration of the hydronium ions directly by

#[H_3O^(+)] = 10^(-14)/([HO^(-)])#

#[H_3O^(+)] = 10^(-14)/(1.9 * 10^(-6)) = 0.53 * 10^(-8) = 5.3 * 10^(-9)"M"#

Here's a diagram that shows how pH, pOH, #[H_3O^(+)]#, and #[OH^(-)]# relate to each other

http://www.sciencegeek.net/Chemistry/taters/Unit8pH.htm