Question

A solution of ammonia NH3(aq) is at equilibrium. How would the equilibrium change if NH4+ were added to the solution?

Answer 1

Answer:

C. The equilibrium would shift to produce more NH₃(g)

Explanation:

NH₃(aq) + H₂O(l) ⇄ NH₄⁺(aq) + OH⁻(aq)

Adding NH₄⁺ to the equilibrium would result in an excess on the product side of the equation and initiate shift to the left until the new equilibrium is established.

Note: Think of the reaction as being on a seesaw, that is ...

NH₃(aq) + H₂O(l) ⇄ NH₄⁺(aq) + OH⁻(aq)

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At equilibrium the seesaw is balanced, but when NH₄⁺ is added, the seesaw is tilted to the right b/c of excess NH₄⁺ and, by natural action, shifts left forming more NH₃ & H₂O in order to form a new balanced equilibrium. :-)