Hydrogen reacts with oxygen: 2H2+O2→2H2O2\mathrm{H_{2}} + \mathrm{O_{2}} \rightarrow 2\mathrm{H_{2}O}2H2+O2→2H2O. A mixture contains 3.0 mol H2\mathrm{H_{2}}H2 and 1.0 mol O2\mathrm{O_{2}}O2. Which statement is correct?
H2\mathrm{H_{2}}H2 is limiting and 3.0 mol H2O\mathrm{H_{2}O}H2O forms
Neither reactant is in excess
O2\mathrm{O_{2}}O2 is limiting and 1.0 mol H2O\mathrm{H_{2}O}H2O forms
O2\mathrm{O_{2}}O2 is limiting and 2.0 mol H2O\mathrm{H_{2}O}H2O forms
55 exam-style questions on Edexcel GCSE Chemistry 2.6 Calculations involving masses, covering 2.6.1 Relative formula mass and percentage composition, 2.6.2 Empirical and molecular formulae, 2.6.3 Conservation of mass, 2.6.4 Reacting masses and concentration in g dm⁻³, 2.6.5 The mole and the Avogadro constant, and 2.6.6 Limiting reactants and stoichiometry. Each one has a worked solution and a mark scheme showing where the marks go.