(a(i))[1]
Give a test and observation that can be used to identify hydrogen gas.
(a(ii))[1]
State one further observation made when zinc is placed in dilute sulfuric acid.
(b(i))[1]
State which experiment has an anomalous reaction time.
(b(ii))[1]
Suggest what the student should do to check whether the reaction time in (b)(i) is anomalous.
(b(iii))[1]
State which experiment has the highest reaction rate.
(b(iv))[1]
Describe how the rate of this reaction changes as the temperature of the dilute sulfuric acid rises.
(c)[1]
State why it is hard to obtain an accurate reaction time at $90\,^{\circ}\text{C}$.
(d)[2]
Suggest two variables, other than the temperature of the dilute sulfuric acid or the mass of zinc, that influence the rate of this reaction.