Chemistry 9701 · AS & A Level · Equilibria

Equilibria — practice question

Ammonia gas, $\text{NH}_3$, combines with hydrogen sulfide gas, $\text{H}_2\text{S}$, to make the salt ammonium sulfide, $(\text{NH}_4)_2\text{S}$. When ammonium sulfide dissolves in water, an orange alkaline solution is produced. $(\text{NH}_4)_2\text{S}(aq) \rightleftharpoons \text{NH}_3(aq) + \text{NH}_4\text{SH}(aq)$ Adding $\text{NaOH}(aq)$ to this solution gives off a gas, $X$. Adding $\text{HCl}(aq)$ to a different portion of the solution produces a gas, $Y$. Which gases are $X$ and $Y$?

  • A$X=\text{H}_2\text{S},\ Y=\text{H}_2\text{S}$
  • B$X=\text{H}_2\text{S},\ Y=\text{NH}_3$
  • C$X=\text{NH}_3,\ Y=\text{H}_2\text{S}$
  • D$X=\text{NH}_3,\ Y=\text{NH}_3$

Worked solution & mark scheme

This 1-mark question has a full step-by-step worked solution and mark scheme.

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI