Long answer·Standard multi-step (3/5)·No calculator
Difficulty guide
The label describes the problem, not your ability.
1/5 - Foundational
Warm-up setup; checks one basic idea.
2/5 - Routine exam skill
Normal syllabus skill; usually one main rule or interpretation.
3/5 - Standard multi-step
Exam-style problem with multiple steps or a common trap.
4/5 - Hard exam skill
High-end exam problem; combines methods carefully.
5/5 - Challenge
Stretch problem beyond normal exam pressure.
Question
Use the purification figure to write a short practical plan for obtaining purer crystals from an impure soluble solid.
Total: 3 marks
(a) Mention the role of hot solvent and hot filtration. (1 mark)
(b) Explain why cooling is done after filtration. (1 mark)
(c) State how melting point can be used to judge improvement in purity. (1 mark)
Something wrong with this item?