(a)[1]
Name the type of metals commonly used as catalysts.
(b(i))[1]
Deduce the volume of hydrogen formed in the first 25 seconds of the experiment.
(b(ii))[1]
Explain why no more hydrogen is produced after 50 seconds.
(b(iii))[2]
Draw a line on the grid to show how the volume of hydrogen changes over time when a catalyst is present. All other conditions remain unchanged.
(b(iv))[2]
Describe what effect the following changes have on the rate of the reaction: - The concentration of hydrochloric acid is decreased. - Large pieces of zinc are used. All other conditions remain the same.
(c(i))[2]
Describe a simple test for hydrogen.
(c(ii))[1]
State one use of hydrogen.