Over millions of years from the fossilised remains of plankton
Where is crude oil found?
In the porous rocks in the Earth's crust
Is crude oil renewable or non-renewable?
Non-renewable
What is crude oil made up of?
Hydrocarbons
What gives hydrocarbon molecules varying properties?
They vary in size
What happens to the properties of hydrocarbons as the molecules get larger?
It gets more viscous, its boiling point gets higher, the less volatile it is, the less easily it ignites
How are the components of crude oil separated?
Fractional distillation
Why does fractional distillation work?
Different sized molecules of hydrocarbons have different boiling points
What piece of equipment does fractional distillation take place in?
Fractionating column
What are the stages of fractional distillation?
1) the crude oil is heated until it evaporates 2) the molecules move up the fractionating column which is hotter at the bottom 3) larger molecules condense at the hotter bottom of the column and are collected 4) the shorter molecules condense at the cooler top of the column and are collected
What is an alkane?
A hydrocarbon in which each carbon molecule makes 4 single bonds with other molecules
Are alkanes saturated or unsaturated?
Saturated
What is the general formula for an alkane?
CnH2n+2
What is the name of an hydrocarbon with 1 carbon molecule?
Meth(ane/ene)
What is the name of an hydrocarbon with 2 carbon molecules?
Eth(ane/ene)
What is the name of an hydrocarbon with 3 carbon molecules?
Prop(ane/ene)
What is the name of an hydrocarbon with 4 carbon molecules?
But(ane/ene)
What is the name of an hydrocarbon with 5 carbon molecules?
Prop(ane/ene)
What happens during the combustion of hydrocarbons?
Carbon and hydrogen are oxidised, energy is released, waste products are released into the atmosphere
What happens in incomplete combustion?
Carbon monoxide is produced which is poisonous. Soot is given off
What is the effect of particulates?
They cause global dimming by reducing the amount of sun that can reach the earth's surface, they cause damage to people's lungs
How are nitrogen oxides produced from combustion?
When high temperatures from combustion are reaches, nitrogen in the air reacts with oxygen
What problems do nitrogen oxides cause?
Cause respiratory problems, react with rainwater to form acid rain
What has been done to try and reduce the amount of sulfur released into the atmosphere?
It can be removed from fuels before combustion in motor vehicles or removed from waste gases in power stationsSee an expert-written answer!We have an expert-written solution to this problem!
What is the balanced symbol equation for complete combustion?
C + O2 = CO2
What is the balanced symbol equation for incomplete combustion?
2C + O2 = 2CO
What is the balanced symbol equation for the combustion of hydrogen?
2H2 + O2 = 2H2O
What is the balanced symbol equation for the combustion of sulfur?
S + O2 = SO2
What is cracking?
Long chain hydrocarbons being split into shorter chain hydrocarbons
What does the process of cracking include?
1) the hydrocarbons are heated until they vaporise 2) the vapour is passed over a hot catalyst 3) thermal decomposition then takes place
What are the products of cracking?
Both alkanes and alkenes
Why are hydrocarbons split into shorter molecules?
There is a higher demand for short hydrocarbons as they easy to ignite and have low boiling points so are used in fuels
What is the main difference between alkenes and alkanes?
Alkenes have a double carbon-carbon bond
What are hydrocarbons that have double bonds described as?
Unsaturated
What is the general formula for an alkene?
C(n)H(2n)
Why are alkenes more reactive than alkanes?
Because of the C=C bond
Why do alkenes burn with a smokier flame than alkanes?
They go through incomplete combustion
What can be added to alkenes to produce alkanes?
Hydrogen
What catalyst is used in the addition reaction used to produce alkanes from alkenes?
Nickel
How can ethanol be produced?
By reacting ethene with steam in the presence of a catalyst- phosphoric acid