A student studies how small magnesium pieces react with excess dilute hydrochloric acid. Mg + 2HCl → MgCl2 + H2. Fig. 8.1 gives the total volume of hydrogen gas, H2, formed as the reaction continues.
(a)[1]
From Fig. 8.1, deduce how long the reaction takes to finish.
(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 H2 produced once the reaction is complete.
(c)[2]
Deduce the type of energy change shown in 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: “119 s” …