Question

Calculate the concentration of OH- in a solution that contains 3.9 x 10-4 M H3O+ at 25°C. Identify the solution as acidic, basic or neutral. Calculate the concentration of OH- in a solution that contains 3.9 x 10-4 M H3O+ at 25°C. Identify the solution as acidic, basic or neutral. 3.9 × 10-4 M, neutral 2.7 × 10-2 M, basic 2.6 × 10-11 M, basic 2.7 × 10-2 M, acidic 2.6 × 10-11 M, acidic

Answer 1

Answer:

[OH⁻] = 2,6x10⁻¹¹

Acidic

Explanation:

The kw in water is:

2 H₂O(l) ⇄ OH⁻(aq) + H₃O⁺(aq)

kw = [OH⁻] [H₃O⁺] = 1,00x10⁻¹⁴

If concentracion of H₃O⁺ is 3,9x10⁻⁴M:

[OH⁻] [3,9x10⁻⁴M] = 1,00x10⁻¹⁴

[OH⁻] = 2,6x10⁻¹¹

pH is defined as - log[H₃O⁺]. If pH>7,0 the solution is basic, if pH<7,0 solution is acidic, if pH=7,0 solution is neutral.

In this problem,

pH = - log [3,9x10⁻⁴M] = 3,4

As pH is < 7.0, the solution is acidic

I hope it helps!

Answer 2

A solution with [OH⁻] = 3.9 × 10⁻⁴ M, is also [H₃O⁺] = 2.6 × 10⁻¹¹ M and it is basic.

What is the ionic product of water?

The ionic product of water, Kw, is the equilibrium constant for the reaction in which water undergoes an acid-base reaction with itself.

We have a solution where the concentration of OH⁻ is 3.9 × 10⁻⁴ M. We can calculate the concentration of H₃O⁺ using the ionic product of water.

Kw = [H₃O⁺][OH⁻]

[H₃O⁺] = Kw / [OH⁻] = 1.0 × 10⁻¹⁴ / 3.9 × 10⁻⁴ = 2.6 × 10⁻¹¹ M

where,

• Kw is the ionic product of water.
• [H₃O⁺] is the concentration of hydronium ions.
• [OH⁻] is the concentration of hydroxyl ions.

Since [H₃O⁺] < 10⁻⁷ M, the solution is basic.

A solution with [OH⁻] = 3.9 × 10⁻⁴ M, is also [H₃O⁺] = 2.6 × 10⁻¹¹ M and it is basic.

Learn more about the ionic product of water here: https://brainly.com/question/15410096