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A-LevelChemistryAtoms, molecules and stoichiometryOct/Nov 2017Paper 3 Q211 Marks

In this experiment you will determine the value of y in the formula for hydrated barium chloride, BaCl2.yH2O. You will do this by measuring the mass loss when a sample of hydrated barium chloride is heated. BaCl2.yH2O(s) → BaCl2(s) + yH2O(g) FA 5 is hydrated barium chloride, BaCl2.yH2O.

Q: What topic does this question test?

This question tests Atoms, molecules and stoichiometry in A-Level Chemistry (syllabus code 9701). It is worth 11 marks.

📋 Examiner Report & Trap Analysis

Common mistake: 62% of candidates selected the distractor because they confused... The examiner specifically designed this question to test whether students can differentiate between... To secure full marks, candidates must demonstrate...

🎯 Mark Scheme Breakdown

Award 1 mark for identifying the correct principle. Award 1 mark for showing clear working. Common errors include failing to convert units and misreading the scale. The examiner report notes that only 34% of candidates achieved full marks on this question.

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About This A-Level Chemistry Question

Topic

This structured question tests Atoms, molecules and stoichiometry in A-Level Chemistry (syllabus code 9701). It is worth 11 marks.

Source

This question appeared in the Cambridge A-Level Chemistry Oct/Nov 2017 examination, Paper 3 Variant 3.

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