A solution has a hydroxide ion concentration of 1 × 10–5 M. What is the hydrogen ion concentration of the solution?

(a) 1 × 10–1 M

(b) 1 × 10–5 M

(c) 1 × 10–9 M

(d) 1 × 10–14 M

The correct answer is (c) 1 × 10⁻⁹ M

Explanation:

Hydroxide ion = OH⁻

Hydrogen ion = H⁺

The autoionization equilibrium of water at 25ºC has a water constant Kw which is expressed as follows:

Kw = [H⁺] x [OH⁻]= 1 x 10⁻¹⁴

If we know the concentration of hydroxide ion ([OH⁻]) we can calculate the hydrogen ion concentration ([H⁺]) as follows:

[H⁺] = Kw/[OH⁻]= (1 x 10⁻¹⁴)/1 x 10⁻⁵ M= 1 x 10⁻⁹ M

h let me think

i think the answer is terrae but not 100 percent sure. ▓▬▬ §