Question

Part A

What is the H+ concentration for an aqueous solution with pOH = 3.26 at 25 ∘C?

Express your answer to two significant figures and include the appropriate units.

Arrange the following aqueous solutions, all at 25 ∘C, in order of decreasing acidity.

Rank from most acidic to most basic. To rank items as equivalent, overlap them.

pOH = 8.55

pH = 5.45

0.0023 M HCl

0.0018 M KOH

Part C

At a certain temperature, the pH of a neutral solution is 7.28. What is the value of Kw at that temperature?

Express your answer numerically using two significant figures.

Answer 1

PART(A)

We know that,

pH + pOH = 14

pH = 14 - 3.26

pH = 10.74

- Log[H⁺] = 10.74

[H⁺] = 1.8 * 10^-11 M

****

(i) pH = 14 - pOH = 14 - 8.55 = 5.45

pH = 5.45

pH = - log[H⁺] = - Log(0.0023) = 2.64

pH = 14 - pOH = 14 + Log[OH] = 14 + Log(0.0018) = 11.26

Hiher the pH value smaller the acidic nature.

0.0023M HCl (1) > pOH =8.55(2) = pH = 5.45 (2) > 0.0018 M KOH (3)

PART (C)

pH = 7.28

- Log[H⁺] = 7.28

[H⁺] = 5.25 * 10^-8 M

Since the solution is noted as neutral solution, [OH^-] = [H⁺] = 5.25 * 10^-8 M

Then, Kw = [H⁺][OH^-]

Kw = 5.25 * 10^-8 * 5.25 * 10^-8

Kw = 2.8 * 10^-15