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5.1 Monitoring chemical reactions

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Question 33

An oxygen generator contains potassium chlorate, KClO3\mathrm{KClO_3}KClO3​. During use, the potassium chlorate decomposes completely.

2KClO3(s)→2KCl(s)+3O2(g) \mathrm{2KClO_3(s) \rightarrow 2KCl(s) + 3O_2(g)} 2KClO3​(s)→2KCl(s)+3O2​(g)

The generator produces 1.80 dm3 of oxygen at room temperature and pressure.

One mole of any gas occupies 24 dm3 at room temperature and pressure.

Relative atomic mass (ArA_rAr​): K = 39.1 Cl = 35.5 O = 16.0

Calculate the mass of potassium chlorate that decomposes.

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Markscheme

5.1 Monitoring chemical reactions Questions

  1. GCSE
  2. /Chemistry
  3. /5.1 Monitoring chemical reactions

152 exam-style questions on OCR GCSE Chemistry 5.1 Monitoring chemical reactions, covering 5.1.1 The technique of titration, 5.1.2 Theoretical mass, percentage yield and atom economy, 5.1.3 Concentration of a solution in mol/dm3, 5.1.4 Concentration calculations and titration results, 5.1.5 Molar gas volume and volumes of gases in reactions, and 5.1.6 Choosing a reaction pathway. Each one has a worked solution and a mark scheme showing where the marks go.

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