Question

In any aqueous solution, the product of the hydronium and hydroxide concentrations will always be equal to ______ at 25°C. This value is known as ______.

Answer 1

In any aqueous solution at 25°C, the product of the hydronium ion concentration and hydroxide ion concentration equals 1.0 × 10−14, known as the ion-product constant for water (Kw).

Step-by-step explanation:

In any aqueous solution, the product of the hydronium ion concentration ([H3O+]) and the hydroxide ion concentration ([OH−]) will always be equal to 1.0 × 10−14 at 25°C. This value is known as the ion-product constant for water (Kw).

For example, in a solution with a hydroxide ion concentration of 0.001 M at 25°C, the hydronium ion concentration can be calculated using the formula [H3O+][OH−]=Kw. Thus, to find the hydronium ion concentration, you would divide Kw by the hydroxide ion concentration, giving you a [H3O+] of 1.0 × 10−11 M.

Similarly, if you had a hydronium ion concentration, you could use the same approach to calculate the hydroxide ion concentration.

In pure water at 25°C, the concentrations of hydronium ions and hydroxide ions are equal because water is neutral. Thus, both [H3O+] and [OH−] in pure water are 1.0 × 10−7 M.