The body's pH is tightly regulated because specific enzymes function best within a narrow pH range. What is the approximate pH of a 1.2 * 10-5 M aqueous solution of NaOH?

9.08

Explanation:

pOH is defined as the negative logarithm of the concentration of hydroxide ions.

Thus,

pOH = - log [OH⁻]

Given that: - [OH⁻] = 1.2 * 10⁻⁵ M

Putting in the above equation as:-

pOH = - log 1.2 * 10⁻⁵ = 4.92

Also, pH + pOH = 14

So, pH = 14 - 4.92 = 9.08

pH scale generally runs from 1 to 14 where pH = 7 represents neutral medium, pH 7 represents basic medium.