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A-LevelChemistryAtoms, molecules and stoichiometryFeb/Mar 2023Paper 1 Q151 Mark

Hydrated cobalt(II) sulfate loses water when heated to give anhydrous cobalt(II) sulfate. All the water of crystallisation is lost to the atmosphere as steam. When 3.10 g of hydrated cobalt(II) sulfate, CoSO₄•xH₂O, is heated to constant mass the loss in mass is 1.39 g. What is the value of x, to the nearest whole number?

A4
B6
C7
D11

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The correct answer is C. This question tests the candidate's understanding of atoms, molecules and stoichiometry within the Chemistrysyllabus. The examiner's mark scheme requires...

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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...

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About This A-Level Chemistry Question

This multiple-choice question appeared in the Cambridge A-Level Chemistry (9701) Feb/Mar 2023 examination, Paper 1 Variant 2. It tests the topic of Atoms, molecules and stoichiometry and is worth 1 mark.

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