The pH of a solution decreases by 2.0. How does the hydronium ion concentration of the solution change? Increases to 2 times the original concentration increases to 100 times the original concentration decreases to one one hundredth. Of the original concentration decreases to one half. Of the original concentration

The hydronium ion concentration increases to 100 times the original concentration

Explanation:

The pH of a solution is defined as the negative logarithm of the hydrogen or hydronium ion concentration of that solution. It is given by the expression below:

pH = -log[H₃O⁺] = log[H₃O⁺]⁻¹

Assuming the solution was at neutral with original pH = 7;

The new pH of the solution will be = 7 - 2 = 5

At pH = 7;

log[H₃O⁺]⁻¹ = 7

[H₃O⁺]⁻¹ = 10⁷

[H₃O⁺] = 10⁻⁷

At pH = 5

log[H₃O⁺]⁻¹ = 5

[H₃O⁺]⁻¹ = 10⁵

[H₃O⁺] = 10⁻⁵

10⁻⁵ = 10⁻⁷ * 10²

But 10² = 100

Therefore, the hydronium ion concentration increases to 100 times the original concentration