Skip to content

Course home

3.2 Use of amount of substance in relation to masses of pure substances

3.2 Use of amount of substance in relation to masses of pure substances

EasyMediumHard
12345678910111213141516171819202122232425262728
Question 25

A student investigated the reaction of iron with bromine gas.

The word equation for the reaction is:

iron+bromine→iron bromide \text{iron} + \text{bromine} \rightarrow \text{iron bromide} iron+bromine→iron bromide

The student weighed:

  • the glass tube
  • the glass tube and iron before the reaction
  • the glass tube and iron bromide after the reaction

The table below shows the student's results:

Mass in g\text{g}g
Glass tube25.30
Glass tube and iron28.10
Glass tube and iron bromide40.10

Calculate the simplest whole number ratio of:

moles of iron atoms:moles of bromine atoms \text{moles of iron atoms} : \text{moles of bromine atoms} moles of iron atoms:moles of bromine atoms

Determine the balanced chemical equation for the reaction.

Relative atomic masses (ArA_rAr​): Br=80\text{Br} = 80Br=80, Fe=56\text{Fe} = 56Fe=56

[6]
Markscheme

3.2 Use of amount of substance in relation to masses of pure substances Questions

  1. GCSE
  2. /Chemistry
  3. /3.2 Use of amount of substance in relation to masses of pure substances

38 exam-style questions on AQA GCSE Chemistry 3.2 Use of amount of substance in relation to masses of pure substances, covering 3.2.1 Moles (HT only), 3.2.2 Amounts of substances in equations (HT only), 3.2.3 Using moles to balance equations (HT only), 3.2.4 Limiting reactants (HT only), and 3.2.5 Concentration of solutions. Each one has a worked solution and a mark scheme showing where the marks go.

Question bank