Answer:
A sample that has low pH, will have a [OH⁻] < 1x10⁻⁷
Explanation:
Kw = 1x10⁻¹⁴
[H₃O⁺] = 1x10⁻⁷
[OH⁻] = 1x10⁻⁷
If pH is very low, [H₃O⁺] > 1x10⁻⁷
For example, [H₃O⁺] = 1x10⁻³ M
- log [H₃O⁺] = pH
- log 1x10⁻³ M = pH = 3
[OH⁻] will be < 1x10⁻⁷
For the example we made before
pH = 3
pOH = 14 - pH → 11
10^-pOH = [OH⁻]
10⁻¹¹ = 1x10⁻¹¹
