Question

What is the pH of a 9.50×10−2 M ammonia solution??

Answer 1

NH₃ + H₂O ⇄ NH₄⁺ + OH⁻

c=9,50*10⁻² mol/L

Ammonia solution is a weak electrolyte.
The dissociation constant of ammonium hydroxide is:
K=1.78*10⁻⁵

[OH⁻]=√(Kc)

pH=14-pOH=14+lg[OH]⁻
pH=14+lg(√(Kc))

pH=14+lg(√(1.78*10⁻⁵*9.50*10⁻²))=8.23
pH=8.23