Question

A certain solution of methylamine has a pOH of 6.8, while a solution of pyridine has a pOH of 6.0. Which solution has a greater concentration of hydroxide ions?

Answer 1

Pyridine solution has a greater concentration of hydroxide ions.

Step-by-step explanation:

The pOH of the solution is defined as negative logarithm of hydroxide ion concentration in a solution.

`pOH=-\log [OH^-]`

• Higher the value of pOH lessor will be the hydroxide ion concentration and higher the concentration of hydrogen ions in the solution .
• Lower the value of pOH higher will be the hydroxide ion concentration and lower the concentration of hydrogen ions in the solution.

1) The pOH of the methylamine = 6.8

`6.8=-\log[OH^-]`

`[OH^-]=1.5848* 10^(-7) M`

2) The pOH of the pyridine = 6.0

`6.0=-\log[OH^-]`

`[OH^-]=0.000001 M=1.0* 10^(-6) M`

Pyridine solution has a greater concentration of hydroxide ions than the solution of methylamine.