During a reaction, 14.0 g of N2\text{N}_2N2 reacts completely with H2\text{H}_2H2. The only product is 17.0 g of NH3\text{NH}_3NH3.
What calculation gives the mass of H2\text{H}_2H2 that reacted?
(17.0 g−14.0 g)×3(17.0\ \text{g} - 14.0\ \text{g}) \times 3(17.0 g−14.0 g)×3
17.0 g+14.0 g17.0\ \text{g} + 14.0\ \text{g}17.0 g+14.0 g
17.0 g−14.0 g17.0\ \text{g} - 14.0\ \text{g}17.0 g−14.0 g
(17.0 g−14.0 g)÷2(17.0\ \text{g} - 14.0\ \text{g}) \div 2(17.0 g−14.0 g)÷2
95 exam-style questions on AQA GCSE Chemistry 3.1 Chemical measurements, conservation of mass and the quantitative interpretation of chemical equations, covering 3.1.1 Conservation of mass and balanced chemical equations, 3.1.2 Relative formula mass, 3.1.3 Mass changes when a reactant or product is a gas, and 3.1.4 Chemical measurements. Each one has a worked solution and a mark scheme showing where the marks go.