How the physical properties of hydrocarbons change with molecule size

2 marks · Normal

State two ways in which refinery gas differs in physical properties from bitumen, another fraction from crude oil.

Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.

Show answer

Also accept: Refinery gas is colourless and very volatile; bitumen is black and not volatile.; Refinery gas burns very easily and is very runny; bitumen does not burn easily and is very viscous.

Show mark scheme and worked solution

Marking points

B1 · 1 mark · Gives one correct difference in a physical property (boiling point, colour, volatility, viscosity, ease of burning).

B2 · 1 mark · Gives a second correct difference in a physical property.

Worked solution

Refinery gas is very volatile and burns easily, whereas bitumen is not volatile and does not burn easily. Also, refinery gas is colourless and runny, while bitumen is black and very viscous.