Topic 4 - Crude Oil and Alternative fuels

These are revision notes on AQA Chemestry1, topic 4 Crude oil and
alternative fuels.

Crude Oil
Crude Oil is a mixture of different length hydrocarbons. These
different lengths are called fractions. We use hydrocarbons
as fuels and for making polymers (plastic).
Because Crude Oil is a MIXTURE the different length…

Properties of different length molecules

Fraction Shorter to longer

Boiling point Increase in temperature

Colour Gets darker


Viscosity Becomes more viscous (sticky)


Volatile Becomes less volatile (sticky)


How easy to burn? less easy to burn











Alkanes
Alkanes are saturated, have only single bonds and are unreactive.
These are the first…

H

2) Ethane C2H6 H H

H C C H

H H

3) Propane C3H8 H H H

H C C C H

H H H

4) Butane (pronounced Buetane)

H H H H

H C C C C H

H H H H
The Chemical formula for Alkanes is…

H H

There is no such thing as Methene because you need at least
TWO carbons to have a double bond and `Meth' means one.

2) Propene C3H6

H H H

H C C C H

H

3) Butene (bueteen) C4H8

H H H H

H C C C C…

However, using crude oil provides us with problems:

CO2 (carbon dioxide) and SO2 (sulphur dioxide) is created
when they are burnt the CO2 contributes to climate
change and the SO2 causes acid rain which can damage
plants, animals, trees and buildings.
The buildup of soot in the atmosphere from burning…

Cons: Engines need to be converted to work with ethanol fuel.
Also ethanol fuel is not widely available and there are worries
that if the demand for it increases farmers will grow fuel crops
rather than food crops leading to increase in food prices.

Biodiesel ­ Produced from vegetable oils…