Organic chemistry

Question 1

What conditions are needed for the manufacture of ethanol from ethene

Answer 1

300 degrees Celsius ,
60-70 pressure atm. ,
phosphoric acid

Question 2

What conditions are needed for the manufacture of ethanol by the fermentation of sugars

Answer 2

Temperature - 30 degrees Celsius

Invertase and zymase - yeast

Question 3

What are the conditions for the dehydration of alcohols

Answer 3

Aluminium oxide

And heat

Question 4

What are the key properties of a homologous series

Answer 4

They have the same general formula
They have similar chemical properties
They have physical properties which show a steady gradation

Question 5

What is a hydrocarbon ?

Answer 5

A compound containing only carbon and hydrogen joined covalently

Question 6

What does saturated mean?

Answer 6

All covalent bonds are single bonds

Question 7

What does unsaturated mean?

Answer 7

Some of the covalent bonds are double or triple bonds

Question 8

What are the conditions needed for catalytic cracking ?

Answer 8

Temperature = 600-700 degrees
Catalyst = silica or alumina

Question 9

What is the general formula for alkanes ?

Answer 9

CnH2n+2

Question 10

What is the general formula for alkenes

Answer 10

CnH2n

Question 11

What are the products of the complete combustion of alkenes ?

Answer 11

Carbon dioxide and water

Question 12

Describe fractional distillation of crude oil

Answer 12

1. Crude oil is heated
2. Heated vapour rises and condenses
3. The fractionating column is cool at the top and warm at the bottom
4. Fractions are condensed and collected at different points along the column depending on their boiling points

Question 13

Which fraction is the most viscous ?

Answer 13

Bitumen

Question 14

What does the reaction of bromine and methane form in the presence of UV light?

Answer 14

Bromomethane

Question 15

What is isomerism ?

Answer 15

The property possessed by certain compounds of have no the same molecular structure but a different arrangement of atoms

Question 16

What are isomers ?

Answer 16

Compounds with the same molecular formula but different arrangement of atoms

Question 17

What problems could the formation of carbon monoxide cause?

Answer 17

Carbon monoxide takes the place of oxygen in red blood cells reducing the oxygen capacity of the blood , which can cause death

Question 18

What problems can nitrogen oxides from the combustion of petrol in car engines at a high temperature cause?

Answer 18

Nitrogen dioxide is an acidic oxide that causes acid rain which
Damages trees
Kills fish and
Corrodes iron structures

Question 19

What type of reaction does Alkane have with Bromine?

Answer 19

Substitution reaction in the presence of UV light

Question 20

What type of reaction is the reaction between alkenes and bromine ?

Answer 20

An addition reaction

Question 21

What is the test for the presence of a carbon carbon double bond?

Answer 21

Bubble the gaseous alkene or liquid alkene in bromine water

If the bromine water turns from orange to colourless there is a carbon double bond

Question 22

What is a polymer ?

Answer 22

A long chain molecule from many monomers joined together

Question 23

What is crude oil ?

Answer 23

A mixture of hydrocarbons