Crude Oil Flashcards
Main information about crude oil
Type of fossil fuel
Finite resource
Formed by plankton buried in mud for millions of years
Time and pressure
What is crude oil a mix of
Hydrocarbons
What are hydrocarbons
Only hydrogen and carbon
C and H atoms joined by covalent bonds to form a homologous family called alkanes
What are alkanes
Hydrogen molecules with single covalent bonds between carbon atoms
Saturated
Used as fuels
General formula for alkanes
CnH2n+2 (n=number of carbons)
Name the first five alkanes and give their molecular formula
And give names of the next five
Methane CH4
Ethane C2H6
Propane C3H8
Butane C4H10
Pentane C5H12
Hexane
Heptane
Octane
Nonane
Decane
How many carbons does petrol have
6-10
What are alkenes
Another homologous family of hydrocarbon molecules with a double C=C bond
Unsaturated
Used as plastics
General formula for alkenes
CnH2n
Properties if the chain length in longer (more hydrocarbons)
Higher boiling point, less volatile, less flammable, high viscosity
Properties of the shorter chain length
Lower boiling point, more flammable, low viscosity, very volatile
What is viscosity?
How easily it flows
What is volatility?
Tendency to turn into gas
What’s a fraction?
Specific length carbon chain within the crude oil mixture
Effect of chain length on intermolecular forces
A longer chain length has more intermolecular forces so for example has a higher boiling point as it requires more energy to break them apart
What’s the products of complete combustion
Carbon dioxide and water
What’s the products of incomplete combustion (insufficient oxygen)
Carbon monoxide & water
What happens to cobalt chloride paper in the presence of water?
Blue to pink
What does the limewater test indicate when it turns cloudy?
The presence of carbon dioxide
What is the function of the ice bath in the products of combustion experiment?
Condense water vapour from the combustion
Describe the setup of the experiment to test the products of combustion.
A candle is burned under a funnel, and the gases produced pass through a U-tube placed in an ice bath. The U-tube contains cobalt chloride paper to test for water. The gases then move into a test tube with limewater to test for carbon dioxide.
