Determine the equilibrium constant for the reaction:
HF(aq) + NH₃(aq) ⇌ NH⁴⁺(aq) + F–(aq)
given the equilibrium constants for the reactions.
HF(aq) + H₂O(l) ⇌ H₃O⁺(aq) + F–(aq) Ka = 6.9×10–4
NH₃(aq) + H₂O(l) ⇌ NH⁴⁺(aq) + OH–(aq) Kb = 1.8×10–5
2H₂O(l) ⇌ H₃O⁺(aq) + OH–(aq) Kw = 1.0×10–14

Question

Determine the equilibrium constant for the  reaction:
HF(aq) + NH3(aq) ⇌ NH4+(aq) + F–(aq)
given the equilibrium  constants for the reactions.
HF(aq) + H2O(l) ⇌ H3O+(aq) + F–(aq) Ka =  6.9×10–4
NH3(aq) + H2O(l) ⇌ NH4+(aq) + OH–(aq) Kb = 1.8×10–5
2H2O(l)  ⇌ H3O+(aq) + OH–(aq) Kw = 1.0×10–14

Accepted Answer

Correct answer: B.

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