AQA A Level Chemistry Year 1 – Alkanes Exam with Questions and Answers –
100% Solved
Describe flue gas desulphurisation - ✔✔✔-Gases passed through a slurry containing calcium
oxide/carbonate.
Neutralise the acidic sulphur dioxide to form calcium sulphite
Describe the structure of a zeolite and suggest why it is important - ✔✔✔-Honeycomb
Large surface area
Explain fractional distillation (4 steps) - ✔✔✔-1. Crude oil is heated to a vapour which passes
into the column
2. The column is hotter at the bottom and cooler at the top
3. Vapours rise up the column and cool, condensing when they meet their boiling point
4. Short chain alkanes are collected near the top as they have lower boiling points
Explain the principles of fractional distillation - ✔✔✔-Different alkanes have different boiling
points depending on their size
Column is cooler at the top
Shorter chain alkanes have lower boiling points
Shorter chain alkanes condense at the top of the column
Give a use of alkanes - ✔✔✔-Fuels
Give the two equations which can occur in flue gas desulphurisation - ✔✔✔-CaO + SO2 -->
CaSO3
CaCO3 + SO2 --> CaSO3 + CO2
Give the two reactions which may happen in a catalytic converter - ✔✔✔-Hydrocarbon + NOx --
> N2 + CO2 + H2O
, AQA A Level Chemistry Year 1 – Alkanes Exam with Questions and Answers –
100% Solved
2NO + 2CO --> 2CO2 + N2
How do nitrogen oxides form? - ✔✔✔-Nitrogen in the air reacts with oxygen at the very high
temperatures of combustion engine
How does a catalytic converter work? - ✔✔✔-Gases pass over the catalyst and react with each
other to produce less polluting products
How does CO form? - ✔✔✔-When carbon in a fuel compound burns in limited oxygen
How does SO2 form? - ✔✔✔-Sulphur impurities in fuel reacts with O2 when hydrocarbons
combust
How might blockage of the air vents in a combustion engine affect its performance? - ✔✔✔-
Less energy given out by the fuel
Engine less powerful/efficient
Methane building up in mines has an explosion risk
Explain why the risk is lower when methane concentration is 15% - ✔✔✔-For an explosive
methane must react with oxygen
Not enough oxygen
What are the conditions for catalytic cracking? - ✔✔✔-800-1000K
1-2 atm
2-4 seconds
Catalyst of aluminosilicate zeolite
100% Solved
Describe flue gas desulphurisation - ✔✔✔-Gases passed through a slurry containing calcium
oxide/carbonate.
Neutralise the acidic sulphur dioxide to form calcium sulphite
Describe the structure of a zeolite and suggest why it is important - ✔✔✔-Honeycomb
Large surface area
Explain fractional distillation (4 steps) - ✔✔✔-1. Crude oil is heated to a vapour which passes
into the column
2. The column is hotter at the bottom and cooler at the top
3. Vapours rise up the column and cool, condensing when they meet their boiling point
4. Short chain alkanes are collected near the top as they have lower boiling points
Explain the principles of fractional distillation - ✔✔✔-Different alkanes have different boiling
points depending on their size
Column is cooler at the top
Shorter chain alkanes have lower boiling points
Shorter chain alkanes condense at the top of the column
Give a use of alkanes - ✔✔✔-Fuels
Give the two equations which can occur in flue gas desulphurisation - ✔✔✔-CaO + SO2 -->
CaSO3
CaCO3 + SO2 --> CaSO3 + CO2
Give the two reactions which may happen in a catalytic converter - ✔✔✔-Hydrocarbon + NOx --
> N2 + CO2 + H2O
, AQA A Level Chemistry Year 1 – Alkanes Exam with Questions and Answers –
100% Solved
2NO + 2CO --> 2CO2 + N2
How do nitrogen oxides form? - ✔✔✔-Nitrogen in the air reacts with oxygen at the very high
temperatures of combustion engine
How does a catalytic converter work? - ✔✔✔-Gases pass over the catalyst and react with each
other to produce less polluting products
How does CO form? - ✔✔✔-When carbon in a fuel compound burns in limited oxygen
How does SO2 form? - ✔✔✔-Sulphur impurities in fuel reacts with O2 when hydrocarbons
combust
How might blockage of the air vents in a combustion engine affect its performance? - ✔✔✔-
Less energy given out by the fuel
Engine less powerful/efficient
Methane building up in mines has an explosion risk
Explain why the risk is lower when methane concentration is 15% - ✔✔✔-For an explosive
methane must react with oxygen
Not enough oxygen
What are the conditions for catalytic cracking? - ✔✔✔-800-1000K
1-2 atm
2-4 seconds
Catalyst of aluminosilicate zeolite
