Question

What of the following is true if the pH of a solution decreases?

[H+] increases
[OH-] increases
Kw increases
Kw decreases
None

Answer 1

[H⁺] increases

Step-by-step explanation:

What of the following is true if the pH of a solution decreases?

• [H⁺] increases. TRUE.

The pH and the [H⁺] are related through the following expression.

pH = -log [H⁺]

According to this, there is an inverse relation between the pH and the [H⁺]. When the pH decreases, the [H⁺] increases.

• [OH⁻] increases. FALSE.

The [H⁺] and the [OH⁻] are inversely related through the following expression.

[H⁺] × [OH⁻] = Kw

As we saw, when the pH decreases, the [H⁺] increases. Then, the [OH⁻] decreases.

• Kw increases. FALSE. Kw is constant at a given temperature.

• Kw decreases. FALSE. Kw is constant at a given temperature.