Question

What is the pH formula?
(A) $-{{\log }_{e}}[{{H}^{+}}]$
(B) $-{{\log }_{10}}[{{H}^{-}}]$
(C) $-{{\log }_{10}}[O{{H}^{-}}]$
(D) $-{{\log }_{10}}[{{H}^{+}}]$

Answer 1

Hint: pH is a special scale which was developed by Sorenson and it shows the presence of protons or hydronium ions present in the solution. If the concentration of protons present in the solution is 10 M, then the pH of the solution is equal to 1.


Complete step by step solution:
Let’s know about pH in order to find its formula.
- pH shows the amount of hydronium ions or protons present in the solution.
- It is a scale of measuring the amount of protons in the solutions which was developed by scientist Sorenson.
- Sorenson said the pH of a solution is a negative logarithmic value of the concentration of protons on the base of 10.
- The H in the pH shows that it shows the concentration of protons present in the solution.
- The formula of pH is as below:
\[pH=-\log [{{H}^{+}}]\]
- The scale of the pH of the solution starts from 0 to 14.
- The pH value of 7 shows that the given solution is neutral in nature.
- If pH of the solution is less than 7, then it means that the concentration of protons present in the solution is high and thus the solution is acidic in nature.
- If pH of the solution is more than 7, then it means that the solution is basic in nature.


So, we can say that correct answer if this question is (D).


Note: Do not get confused between pH and pOH of the solution. pOH of the solution shows the amount of hydroxide ions present in the solution. However, pH and pOH of the solution are related by following formulas and we can find either of them if the other is known.
\[pH+pOH=14\]