Organic Chemistry Revision

Grade 10

What is crude oil?

It is a mixture of hydrocarbons.

How was crude oil formed?

• From the buried remains of

animals and plants

• over millions of years

• High pressure and

temperature.

What are hydrocarbons?

Are compounds made up of hydrogen and carbon only.

What is the name of the process used for separating crude oil?

Fractional distillation

What is the name of the apparatus used for separating crude oil?

Fractionating column

Name four fractions produced by fractional distillation.

Refinery gas

Petrol

Gasoline

Kerosene

Diesel bitumen

Referring to the size of the hydrocarbon, which one fraction will be collected at the top? At the bottom of the fractionating tower?

Short fractions at the top

Long fractions at the bottom

What are the products of the complete combustion of a hydrocarbon?

Carbon dioxide and water vapour

What are the products of the incomplete combustion of a hydrocarbon?

Carbon monoxide and water vapour

What is the name of the poisonous gas produced by incomplete combustion?

Carbon monoxide

What is the effect of this gas on health?

Carbon monoxide is a poisonous gas.

It decreases the oxygen carriers in blood.

It may cause death if its level in blood is high.

How can you break long chain hydrocarbons?

By cracking

What is the difference between cracking and fractional distillation?

Cracking is a chemical process while fractional distillation is a physical process.

What are the conditions for cracking?

High temperature

catalyst

What is a homologous series?

Members of the series have the Same general formula.

Similar chemical properties Successive members differ by CH2 similar physical properties such as appearance, melting/boiling points,

What is the general formula of alkanes?

Cn H2n+2

What is the general formula of alkenes?

Cn H2n

Give the molecular formula of:ethanepropenebutenemethane

C2 H6

C3 H6

C4 H8

C H4

Draw the structural formula of propane

Draw the structural formula of butene

What is the chemical test used to differentiate between alkanes and alkenes? what is the result?

Bromine water test

The bromine will decolorize in alkenes and stays orange brown in alkanes.

Write the polymerization reaction of polyethene.

C Cn C C

n

Name two other polymers and draw their monomers then name them.

Polypropene

polychloroethene

C C

H CH3

HH

C C

H Cl

HH