Given a solution with a hydroxide ion concentration oh = 2.73 * 10-5 what is the ph

We know that,

pH = - log [H+] and pOH = - log [OH-]

When water is used as a solvent pH + pOH = 14

Given [OH-] = 2.73 X 10-5 mol/dm3

∴ pOH = - log (2.73 X 10-5)

= 5

Thus, pH = 14 - pOH - 14 - 5 = 9

Here, ∵ pH is > 7, it suggest that solution is basic in nature.