Methane is the main gas in natural gas. Methane burns completely in oxygen.
CH4+2O2→CO2+2H2O \mathrm{CH_{4}} + 2\mathrm{O_{2}} \rightarrow \mathrm{CO_{2}} + 2\mathrm{H_{2}O} CH4+2O2→CO2+2H2OAll gas volumes in this question are measured at room temperature and pressure.
State the volume occupied by one mole of any gas at room temperature and pressure.
120 cm3\mathrm{cm^{3}}cm3 of methane burns completely.
Calculate the volume of oxygen that reacts and the volume of carbon dioxide made.
Volume of oxygen = ...... cm3\mathrm{cm^{3}}cm3
Volume of carbon dioxide = ...... cm3\mathrm{cm^{3}}cm3
Calculate the volume of 3.2 g of oxygen gas, O2\mathrm{O_{2}}O2.
Relative atomic mass (Ar): O = 16.0
Volume = ...... dm3\mathrm{dm^{3}}dm3
Calculate the mass of carbon dioxide made when 6.0 dm3\mathrm{dm^{3}}dm3 of methane burns completely.
Relative atomic mass (Ar): C = 12.0 O = 16.0
Mass = ...... g
A balloon contains 2.4 dm3\mathrm{dm^{3}}dm3 of helium. A second balloon contains 2.4 dm3\mathrm{dm^{3}}dm3 of carbon dioxide. Both balloons are at the same temperature and pressure.
A student says, "The carbon dioxide balloon contains more molecules, because carbon dioxide molecules are heavier than helium atoms."
Explain why the student is wrong.
57 exam-style questions on OCR GCSE Chemistry 5.1 Monitoring chemical reactions, covering 5.1.1 The technique of titration, 5.1.2 Theoretical mass, percentage yield and atom economy, 5.1.3 Concentration of a solution in mol/dm3, 5.1.4 Concentration calculations and titration results, 5.1.5 Molar gas volume and volumes of gases in reactions, and 5.1.6 Choosing a reaction pathway. Each one has a worked solution and a mark scheme showing where the marks go.