Final answer:
The two errors are using dilute sulphuric acid instead of hydrochloric acid and applying heat to the reaction which is not necessary as zinc and dilute acids react exothermically.
Step-by-step explanation:
The student has made two errors in setting up the experiment to prepare and collect dry hydrogen gas. The first error is using dilute sulphuric acid with zinc. Whilst sulphuric acid will react with zinc and produce hydrogen gas, the standard method for producing hydrogen in the laboratory setting often involves using dilute hydrochloric acid to react with zinc granules.
The second error is the mention of heat. When zinc is reacted with a dilute acid like hydrochloric acid at room temperature, it generally does not require an external heat source, as the reaction is exothermic and will proceed with the generation of heat.
Zinc reacts with dilute hydrochloric acid to form zinc chloride and hydrogen gas according to the equation:
Zn(s) + 2HCl(aq) → ZnCl₂(aq) + H₂(g)
This reaction is different from the one hinted at in the subsequent steps that generate carbon dioxide gas, which likely involves a carbonate reacting with an acid.