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Purpose of filtering excess solid
A student produced a salt by reacting copper carbonate with sulfuric acid.
- Measure 50 cm³ of sulfuric acid into a beaker.
- Add copper carbonate powder.
- Stir the mixture.
- Repeat steps 2 and 3 until copper carbonate is in excess.
- Filter the mixture.
- Warm the filtrate gently until crystals start to appear.
- Leave the solution to cool and crystallise.
Give one reason for filtering the mixture in Step 5.
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Marking points
- 1 Explains that filtration removes the excess copper carbonate solid.
Full-mark answer
To remove the excess copper carbonate from the mixture.
Why this answer loses marks
Filtering makes the reaction go faster.
The reaction is already complete; filtering separates the excess solid from the solution.