Biodiesel

Question 1

What is an example of a solid ester?

Answer 1

animal fats

Question 2

What is an example of a liquid ester?

Answer 2

vegetable oils

Question 3

What is biodiesel?

Answer 3

a mixture of methyl esters of long-chain carboxylic acids, formed in a transesterification reaction

Question 4

How can you convert vegetable oil into biodiesel?

Answer 4

by reaction with methanol in the presence of a catalyst

Question 5

What is a transesterification reaction?

Answer 5

a reversible reaction in which an ester reacts with an alcohol in excess to form a new ester and a new alcohol

Question 6

What is the equation for the transesterification of biodiesel?

Answer 6

triglycerides + 3methanol ⇌ (acid/base catalyst) 3 methyl esters of long chain fatty acids + glycerol

Question 7

Why does transesterification require an excess of methanol?

Answer 7

its a reversible reaction so an excess of methanol is used to drive the equilibrium to the right to make more biodiesel

Question 8

How is biodiesel made less viscous?

Answer 8

converting vegetable oil into methyl esters

Question 9

Why is biodiesel better for the environment?

Answer 9

cleaner burning, biodegradable and non-toxic

Question 10

Why might biodiesel lead to a food shortage?

Answer 10

farmers might stop planting staple food crops in favour of biodiesel cash crops