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3.1 Introducing chemical reactions

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Question 29

A sealed flask contains a mixture of 2.30 g of nitrogen dioxide, NO2\mathrm{NO_2}NO2​, and 1.60 g of oxygen, O2\mathrm{O_2}O2​.

A sample bottle contains 2.50 g of carbon, C\mathrm{C}C.

Relative atomic mass (ArA_rAr​): C = 12.0, N = 14.0, O = 16.0

Avogadro constant = 6.02×1023 mol−16.02 \times 10^{23}\,\mathrm{mol^{-1}}6.02×1023mol−1

Calculate whether the flask or the sample bottle contains the greater total number of atoms, and how many more atoms it contains. Show your working.

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Markscheme

3.1 Introducing chemical reactions Questions

  1. GCSE
  2. /Chemistry
  3. /3.1 Introducing chemical reactions

134 exam-style questions on OCR GCSE Chemistry 3.1 Introducing chemical reactions, covering 3.1.1 Writing formulae and balanced chemical equations, 3.1.2 Formulae of compounds from ions, and state symbols, 3.1.3 Conservation of mass and observed changes in mass, 3.1.4 Half equations and balanced ionic equations, 3.1.5 The mole and the Avogadro constant, and 3.1.6 Stoichiometry, limiting reactants and reacting masses. Each one has a worked solution and a mark scheme showing where the marks go.

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