Question

How do you convert between $pH$ , $pOH$ , $[H^+ ]$ and $[OH^- ]$ ?

Answer 1

To solve this question, we will do the conversion of any of the given component with $pH$ into any other of the given components by applying logarithm or by using 10 as the base and the given component as the exponent of 10.

Complete step by step solution:
There are many different ways involved during the conversion of the given components on a $pH$ :
(i) $[{H^+ }] \to pH$
As we apply $- \log$ in $[H^+ ]$ :
$- \log [{H^ + }] = pH$
(ii) $[O{H^ - }] \to pH$
As we apply $- \log$ in $[OH^- ]$ :
$- \log [O{H^ - }] = pOH$
(iii) $pH \to [{H^ + }]$
As we apply 10 as a base and $- pH$ as the exponent:
${10^{ - pH}} = [{H^ + }]$
(iv) $pOH \to [O{H^ - }]$
As we apply 10 as a base and $- pOH$ as the exponent:
${10^{ - pOH}} = [O{H^ - }]$
(v) If we subtract $pH$ from 14:
$14 - pH = pOH$
(vi) If we subtract $pOH$ from 14:
$14 - pOH = pH$ .

Note:
$pH$ and $pOH$ are two terms used to express the acidity or alkalinity of a solution. The main difference between $pH$ and $pOH$ is that $pH$ is a measure of hydrogen ions whereas $pOH$ is a measure of hydroxide ions.