Alkanes

Question 1

Explain how oxides of nitrogen are formed

Answer 1

Nitrogen and oxygen (from air) react at high temperatures

Question 2

Both C3H8 and C4H10 can be liquified and used as fuels for camping stoves. Suggest, with a reason, which of these two fuels is liquified more easily.

Answer 2

C4H10 - it has a higher boiling point and stronger intermolecular forces

Question 3

Explain why the complete combustion of C4H10 may contribute to environmental problems. (1 mark)

Answer 3

It produces CO2 and H2O which are both greenhouse gases

Question 4

Identify a compound that is used to react with the sulfur dioxide in the products of combustion before they enter the atmosphere. Give one reason why this compound reacts with sulfur dioxide.

Answer 4

CaO or CaCO3 - neutralises the SO2

Question 5

State the type of cracking that produces a high proportion of ethene and propene. Give the two conditions for this cracking process. (2 marks)

Answer 5

Thermal cracking - high pressure and high temperature