Ask Question
11 November, 05:44

A solution of ammonia has a pH of 10.50. what is the initial molarity of ammonia? Kb for ammonia is 1.8x10^-5

+4
Answers (1)
  1. 11 November, 08:16
    0
    5.55 x 10⁻³ mol/L.

    Explanation:

    ∵ pH + pOH = 14.

    ∴ pOH = 14 - pH = 14 - 10.50 = 3.5.

    ∵ pOH = - log[OH⁻].

    ∴ - log[OH⁻] = - 3.5.

    ∴ [OH⁻] = 3.16 X 10⁻⁴.

    ∵ [OH⁻] = √ (kb) (c)

    kb = 1.8 x 10⁻⁵.

    c is the initial concentration.

    3.16 X 10⁻⁴ = √ (1.8 x 10⁻⁵) (c).

    by squaring both sides:

    (3.16 X 10⁻⁴) ² = (1.8 x 10⁻⁵) (c).

    1.0 x 10⁻⁷ = (1.8 x 10⁻⁵) (c)

    ∴ c = (1.0 x 10⁻⁷) / (1.8 x 10⁻⁵) = 5.55 x 10⁻³ mol/L.
Know the Answer?
Not Sure About the Answer?
Get an answer to your question ✅ “A solution of ammonia has a pH of 10.50. what is the initial molarity of ammonia? Kb for ammonia is 1.8x10^-5 ...” in 📙 Chemistry if there is no answer or all answers are wrong, use a search bar and try to find the answer among similar questions.
Search for Other Answers