Alkanes
Alkenes
Crude Oil
Fractional Distillation
Cracking
100
Define "hydrocarbon"
Molecule composed of only hydrogen and carbon atoms
100
Define "unsaturated" hydrocarbon
Hydrocarbon with a carbon-carbon (C=C) double bond
100
What is crude oil and how was it formed?
Crude oil is a mixture of hydrocarbons of varying lengths.
It was formed millions of years ago from the remains of dead sea creatures, etc.
100
What is fractional distillation and why is it done?
Fractional distillation is the separation of hydrocarbons of varying lengths into fractions, and it is done by using their boiling points to separate.
100
What is cracking?
The breakdown of long hydrocarbons into shorter, hydrocarbons [ie. alkanes & alkenes]
200
Define "isomer"
Same molecular formula, different structural formula
200
List 3 properties of a "homologous series" of alkenes
Any 3 of:
- differ by one "-CH2-"
- similar chemical properties
- trend in physical properties
- same functional group
200
Which 2 elements contribute to acid rain?
Sulfur & nitrogen
200
What is the temperature gradient in the fractioning column?
Hot at the bottom, cool at the top
200
Why is cracking done?
Cracking is done to attain more in demand, useful, shorter-alkanes and alkenes
300
What type of reaction is this? And what is required for it to occur?
C2H6 + Br2 -->
Type: substitution
Required: UV light
300
What are the uses of alkenes?
To make polymers
300
What environmental issue is caused by combustion of fossil fuels with sulfur?
Acid Rain
300
Give the name of fraction used as aeroplane fuel
Kerosene
300
What are the traditional products of cracking (list all 3 potential ones) & what is the uses of them?
Potential products: alkane, alkene, hydrogen
Use of alkenes: polymers :D
400
Explain why the boiling point of octane is higher than hexane.
Hint: 2 points need to be made
Octane has a higher relative molecular mass than hexane, therefore it has stronger intermolecular forces between molecules.
As a result, more energy is needed to overcome the force.
400
What is the product for the following reaction:
C2H4 + Br2 -->
C2H4Br2
400
What toxic gas is produced for incomplete combustion & why is it toxic?
Gas: carbon monoxide
Toxic: reduces capacity of blood to carry oxygen
400
What is the use of bitumen, and where does it condense?
Use: making roads
Condenses: high BP so condenses at the bottom
400
Predict the product of the following equation:
C10H22 --> C2H4 + ?
C8H18
500
Name the following alkane:
2,3-dimethylbutane
500
What are alkenes, precursors to make polymers used for?
To make plastic
500
How is acid rain formed?
Hint: 3 points
1. Sulfur impurities burned/undergo combustion
2. Sulfur + O2 --> SO2
3. 2 SO2 + O2 + 2 H2O --> 2 H2SO4
500
How is crude oil separated into fractions?
Hint: 4 points to be made
1. Fractional distillation is used --> or reference to use of fractioning column
2. Crude oil is vaporized (so it can travel up the column)
3. Fractioning column has a temperature gradient --> hottest at bottom
4. Fractions condense at different heights --> shortest condense at the top or vice versa
500
What are the conditions for "catalytic cracking"?
Hint: 3 points
Temperature: 600 - 700 degrees
Catalyst: Alumina, Silica