Questions on Energy Sources

Q6. The table below gives information about three fuels that can be used in cars. shows a substance is produced when the fuel burns. X shows a substance is not produced when the fuel burns.

fuel

 

physical state

 

energy released, in kJ/kg

 

some of the substances produced when the fuel burns

carbon monoxide

sulphur dioxide

water

petrol

liquid

48 000

hydrogen

gas

121 000

X

X

ethanol (alcohol)

liquid

30 000

X

(a) Which fuel, in the table, releases the least energy per kilogram (kg)?

1 mark

(b) Some scientists say that if hydrogen is burned as a fuel there will be less pollution. From the information in the table, give one reason why there will be less pollution.

1 mark

(c) Which of the three fuels in the table can be compressed into a small container?

1 mark

(d) Which gas in the air is needed for fuels to burn?

1 mark

(e) Petrol and ethanol are both fuels. Petrol is made from oil. Scientists say that oil could run out in 100 years. In some countries people plant sugar cane and use it to make ethanol. Sugar cane will not run out. Explain why.

1 mark

Maximum 5 marks