Question Constellation Sign up for free AQA · GCSE · Chemistry · Higher
Using excess copper carbonate
A student prepared copper sulfate by reacting an acid with excess copper carbonate.
Figure 3 shows the first two stages in the preparation of copper sulfate.
Why is excess copper carbonate used in stage 1?
Write your answer first. You can study the marking guidance whenever you need it.
Study the marking See what earns credit and compare it with a full-mark answer.
Marking points
- 1 Explains that the excess ensures all of the acid reacts or is used up.
Full-mark answer
It ensures that all of the acid reacts and is used up.
Why this answer loses marks
The excess makes the reaction faster.
Reaction rate is not the reason credited here; the excess is used so that all of the acid reacts.