Alkenes

Sugar can be fermented to produce ethanol.
Some of the stages in the process to produce and purify ethanol are listed.

1 Leave in a warm place.
2 Add yeast.
3 Fractionally distil the solution.
4 Dissolve the sugar in water.
5 Filter to remove the yeast.
6 Crush some sugar cane.

What is the correct order of these stages?

Propanol is oxidised by acidified potassium manganate(VII) in a similar way to ethanol.
Which compound is produced by the oxidation of propanol with acidified potassium manganate(VII)?

What is not essential for the formation of ethanol by fermentation?

Substance $Z$ has the following characteristics.

1 It burns in an excess of oxygen to form carbon dioxide and water.
2 It is oxidised by air to form a liquid smelling of vinegar.
3 It reacts with carboxylic acids to form esters.

What is substance $Z$ ?

The diagram shows a reaction sequence.

Which row names the processes X, Y and Z ?

$$\begin{array}{|c|c|c|c|} \hline & \mathrm{X} & \mathrm{Y} & \mathrm{Z} \\ \hline \text { A } & \text { cracking } & \text { fermentation } & \text { respiration } \\ \text { B } & \text { cracking } & \text { hydration } & \text { combustion } \\ \text { C } & \text { distillation } & \text { fermentation } & \text { respiration } \\ \text { D } & \text { distillation } & \text { hydration } & \text { combustion } \\ \hline \end{array}$$

Ethanol is manufactured from petroleum by reacting ethene with steam.
Which statements about this process are correct?

1 Ethene is obtained from the cracking of alkanes.
2 The process is carried out in the presence of yeast.
3 The reaction is an addition reaction.
4 The rate of reaction is increased by a catalyst.

 Which row describes an advantage and a disadvantage of making ethanol by fermentation? 

$$\begin{array}{|c|c|c|} \hline & \text { advantage } & \text { disadvantage } \\ \hline \text { A } & \text { uses a renewable resource } & \text { occurs at a slow rate } \\ \text { B } & \text { needs a high temperature } & \text { produces impure ethanol as a product } \\ \text { C } & \text { produces pure ethanol as a product } & \text { needs a high temperature } \\ \text { D } & \text { occurs at a slow rate } & \text { uses a non-renewable resource } \\ \hline \end{array}$$

The diagram shows a reaction sequence.

Which row names the processes X, Y and Z ?

$$\begin{array}{|c|c|c|c|} \hline & \mathrm{X} & \mathrm{Y} & Z \\ \hline \text { A } & \text { cracking } & \text { fermentation } & \text { respiration } \\ \text { B } & \text { cracking } & \text { hydration } & \text { combustion } \\ \text { C } & \text { distillation } & \text { fermentation } & \text { respiration } \\ \text { D } & \text { distillation } & \text { hydration } & \text { combustion } \\ \hline \end{array}$$

The structure of compound R is shown.

What is R?

Ethanol can be formed by:

1 fermentation
2 reaction between steam and ethene.

Which of these processes use a catalyst?

$$\begin{array}{|c|c|c|} \hline & 1 & 2 \\ \hline \text { A } & \checkmark & \checkmark \\ \text { B } & \checkmark & x \\ \text { C } & x & \checkmark \\ \text { D } & x & x \\ \hline \end{array}$$

The table shows the boiling points of four members of the homologous series of alcohols.

What is the value of X ?

Ethanol is made by fermentation of sugars and by the catalytic addition of steam to ethene.
What are two advantages of making ethanol by the catalytic addition of steam to ethene rather than by fermentation of sugars?