What is the hydroxide concentration of a 0.10 molar solution of ammonia at equilibrium if its ka is 5.62 × 10-10?

7.5 × 10 ⁻⁶ M

Explanation:

1) Equlibrium equation:

NH₃ + H₂O ⇄ NH₄⁺ + OH⁻

2) Mole balance

                      NH₃               NH₄⁺ + OH⁻

Start              0.1                   0         0
React             x                      0        0
Produced       0                      x         x
Final              0.1 - x              x         x

3) Ka equation: Ka = [NH₄⁺] [ OH⁻] / [NH₃] = x² / (0.1 - x) = 5.6 × 10 ⁻¹⁰

4) You can solve that equation easily if you realize tha x is so small that 0.1 - x ≈ 0.1

⇒ x² / 0.1 ≈ 5.6 × 10 ⁻¹⁰

⇒ x = √ ( 5.6 × 10 ⁻¹¹) = 7.50 × 10⁻⁶ M = [OH⁻]

Non metal is an element or substance that is not a metal metal is a solid material that is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivitymetalloid is an element (e.g., germanium or silicon) whose properties are intermediate between those of metals and solid nonmetals. they are electrical semiconductors.