An excess of dilute hydrochloric acid is poured into aqueous sodium sulfide, forming aqueous sodium chloride and hydrogen sulfide gas, H2S. $2HCl(aq)+Na_2S(aq)\rightarrow 2NaCl(aq)+H_2S(g)$. Fig. 8.1 gives the overall volume of hydrogen sulfide gas, H2S, produced as the reaction continues.
(a)[1]
Use Fig. 8.1 to determine the total volume of H2S produced by the time the reaction is complete.
(b(i))[1]
State the effect, if any, on the time needed for the reaction to finish.
(b(ii))[1]
State the effect, if any, on the total volume of H2S produced when the reaction is complete.
(c)[2]
Deduce the kind of energy change shown by the diagram in Fig. 8.2. Explain your answer.
Worked solution & mark scheme
This 5-mark question has a full step-by-step worked solution and mark scheme. One marking point: “132.5 cm^{3}” …