Crude oil - making, problems and uses Flashcards
How is crude oil formed?
How is it extracted?
The buried remains of plants and animals turns into this over millions of years
Drilling and pumping
Crude oil is a mixture
What is a mixture?
What is crude oil a mixture of?
Something that contains two or more elements or compounds that aren’t chemically bonded to each other
Different compounds, mostly hydrocarbon molecules
How can crude oil be separated out into its different compounds?
Physical methods - fractional distillation
What does each fraction contain?
Molecules with similar numbers of carbon atoms
How does the fractional distillation process work? (3)
(Working continuously) - the crude oil is heated and piped into the bottom of the column
The vapourised fuel rises up the column
The fractions are tapped off where they condense
What is the order and the names of the fractions produced? Start from the bottom (7)
The length of the molecules gets ….. as you go up the column.
Bitumen - for roads Oil - for joints etc Diesel - lorries Kerosene - jet fuel Naptha - chemicals Petrol - cars Refinery gas, bottle gas - for homes etc burning Shorter
All the fractions of crude oil are …..
hydrocarbons called alkanes
What are alkanes?
Chains of carbon atoms, surrounded by hydrogen atoms on every bond a carbon has spare (4)
What are the first 4 alkanes?
What is their formula?
Methane CH4
Ethane C2H6
Propane C3H8
Butane C4H10
The carbons form ….. bonds and hydrogen forms …. bond in an alkane.
This is called being …..
What is the alkane general formula?
4, 1
saturated
Cn H2n+2
The shorter the hydrocarbon molecules the: (3)
more runny it is and less viscous
more volatile it is: turn into a gas at a lower temperature , so lower boiling point
more flammable it is
What is refinery gas’s useful property?
Why does it have the lowest boiling point?
How is it stored, under what in what?
What happens when it is used with a burner?
It is so volatile it is a gas at room temperature
because it has the shortest hydro c chains
Under pressure as liquid in bottles, bottled gas
The cap is removed, it vaporizes and flows into the burner where it’s ignited.
The petrol fraction has longer molecules so it has a …
Petrol is in the state of a …. which is ideal for…
What happens to it when it is used in a car?
higher boiling point
liquid
storing in cars
It flows into the engine where it is easily vapourised to mix with the air before it’s ignited
What does viscous mean?
How this this decide how different fractions are used?
having a thick, sticky consistency between solid and liquid
Really gloopy HCarbons are used for lubricating engine parts or covering roads.
Why do crude oil fractions make good fuels?
Where are the fractions used? (3)
They burn cleanly
In transport and central heating systems/power stations to generate electricity