Biofuels

Question 1

What is a biofuel?

Answer 1

A biofuel is a fuel produced from plants.

Question 2

What does the term carbon neutral refer to?

Answer 2

An activity that has no net annual carbon (greenhouse gas) emissions to the atmosphere.

Question 3

How can it be argued that ethanol produced by fermentation is a carbon-neutral activity?

Answer 3

Because any carbon dioxide given off when the biofuel is burnt would have been extracted from the air by photosynthesis when the plant grew. There would be no net CO2 emissions in the atmosphere.

Question 4

What does fermentation to produce ethanol not take into account?

Answer 4

Any energy needed to irrigate plants, fractionally distil the ethanol from the reaction mixture or process the fuel. If the energy for these process comes from fossil fuels then the ethanol produced is not carbon neutral.

Question 5

Write the equations to show that fermentation is carbon neutral.

Answer 5