Alcohols

Question 1

Advantages for fermentation of sugars

Answer 1

1. it is a low-technology process, which means it can be used anywhere
2. it does not use much energy
3. it uses sugar cane as a raw material, which is a renewable resource

Question 2

Disadvantages for fermentation of sugars

Answer 2

1. it is a batch process, which means that once the reaction has finished the vessel needs to emptied before the reaction can be started again
2. it is a relatively slow process
3. it produces fairly impure ethanol

Question 3

Advantages for hydration of ethene

Answer 3

1. it is a relatively fast process
2. it is a continuous flow process, which means that ethene can be entered into the vessel continuously and the reaction never has to be stopped
3. it produces pure ethanol

Question 4

Disadvantages for hydration of ethene

Answer 4

1. it requires fairly high technology
2. it uses a lot of energy
3. the ethene comes from crude oil, which is a non-renewable resource

Question 5

Biofuel

Answer 5

A fuel derived or produced from renewable biological sources

Question 6

Carbon-neutral

Answer 6

Although they release carbon dioxide when they are burned, they come from plant sources which absorb carbon dioxide from the atmosphere during photosynthesis while they are growing. Thus there are no net emissions of carbon dioxide during the process from growing to combustion.

Question 7

Primary alcohol to aldehyde

Answer 7

Reagent: potassium dichromate and dilute sulphuric acid
Conditions: warm, distillation

Question 8

Secondary alcohol to ketone

Answer 8

Reagent: potassium dichromate and dilute sulphuric acid
Conditions: heat, distillation

Question 9

Aldehyde to carboxylic acid

Answer 9

Reagent: potassium dichromate and dilute sulphuric acid
Conditions: heat, reflux

Question 10

Alcohols to alkenes

Answer 10

Reagent: concentrated sulphuric acid
Conditions: heat