C7 Flashcards
What is crude oil?
A finite resource found in rocks.
The remaining of ancient biomass made of plankton that was buried in mud.
Therefore, a mixture of a large number of compounds which are mostly hydrocarbons.
What is a hydrocarbon?
A compound only containing hydrogen and carbon atoms.
What is the general formula for an alkane?
CnH2n+2
What is the name of an alkane containing 1 carbon atom?
Methane
What is the name of an alkane containing 2 carbon atoms?
Ethane
What is the name of an alkane containing 3 carbon atoms?
Propane
What is the name of an alkane containing 4 carbon atoms?
Butane
How can the hydrocarbons in crude oil be separated?
Fractional Distillation
What uses do we have for the fractions of crude oil?
Fuels and the petrochemical industry
What fuels are produced from crude oil?
Petrol, Diesel, Kerosene, Heavy Fuel Oil, Liquified Petroleum Gases
What materials are produced by the petrochemical industry?
Solvents, lubricants, polymers, detergents
Why are there lots of natural and synthetic carbon compounds?
The ability of carbon atoms to form families of similar compounds.
What happens during fractional distillation?
The crude oil is heated and evaporates.
As the gas rises it cools and condenses at its boiling where it can then be collected.
What properties of a hydrocarbon depend on its size?
Flammability, viscosity and boiling points
What happens to the flammability of a hydrocarbon as it becomes larger?
Decreases
What happens to the viscosity of a hydrocarbon as it becomes larger?
Increases
What happens to the melting and boiling point of a hydrocarbon as it becomes larger?
Increases
What happens during combustion of hydrocarbon fuels?
The carbon and hydrogen in the fuel are fully oxidized to make carbon dioxide and water.
This releases energy.
What is the word equation for combustion of a fuel from crude oil?
Hydrocarbon + Oxygen Carbon Dioxide + Water
How can hydrocarbons be broken down into smaller molecules?
Cracking
What happens during catalytic cracking?
The crude oil is vaporized and passed over a hot catalyst.
What happens during steam cracking?
The crude oil is vaporized and mixed with steam and heated to a high temperature.
What are the products of cracking?
Smaller useful alkanes and alkenes
How can we test for alkenes?
Add bromine water and if the colour changes to clear, an alkene is present.
What colour change happens when alkenes react with bromine?
The orange bromine water turns colourless.
