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3.1 Introducing chemical reactions

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Question 1

A student heats a mixture containing 15.96 g of iron(III) oxide and 5.60 g of carbon monoxide until no further reaction takes place.

Fe2O3+3CO→2Fe+3CO2 \mathrm{Fe_2O_3 + 3CO \rightarrow 2Fe + 3CO_2} Fe2​O3​+3CO→2Fe+3CO2​

Relative atomic mass (ArA_rAr​): C = 12.0 O = 16.0 Fe = 55.8

When the reaction stops, which reactant is left over, and what is the greatest mass of iron that can form?

[1]
A

Iron(III) oxide remains; 3.72 g

B

Carbon monoxide remains; 11.2 g

C

Carbon monoxide remains; 5.58 g

D

Iron(III) oxide remains; 7.44 g

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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