Unit 20 & 21 - Fuels/ Earth And Atmospheric Science Flashcards
How are natural gas and crude oil formed from?
Remains of microscopic animals and plants in the sea that had layers on sediment on top
What are finite resources
Resources that are not made any more
What is crude oil?
A complex mixture of hydrocarbons
What is a hydrocarbon?
A compound that contains hydrogen and carbon atoms
What state is crude oil at room temp?
Liquid
Give 2 uses of crude oil
Fuels for vehicles, feedstock or raw materials
What are petroleum Chemicals?
Substances made from crude oil such as poly(ethene)
What is natural gas?
A mixture of hydrocarbons in a gas state
What is the main hydrocarbon in natural gas?
Methane
What is methane used for
Cooking
What is petrol and diesel oil used for
Fuel in vehicles
What is kerosene used for
Fuel in aircrafts
What is diesel used for
Fuel in some cars and trains
What is fuel oil used for
Fuel for large ships and power stations
What is bitumen used for
Surfacing roads and roofs
In terms of number of bonds, which hydrocarbons have the lowest boiling points?
With the least number of bonds
In terms of number of bonds, which hydrocarbons have the highest viscosity
With the highest number of bonds
In terms of number of bonds, which hydrocarbons are easiest to ignite
With lower number of bonds
Are compounds in crude oil mostly alkenes or alkanes
Alkanes
What is a combustion reaction?
When hydrocarbon fuels are reacted with oxygen
What is complete combustion?
A combustion reaction where only CO2 and water are produced, energy is given out, there is enough oxygen
What is the main hydrocarbon found in natural gas?
Methane
How can you test for an alkane?
Combustion reaction with enough oxygen, the CO2 produced should make limewater turn cloudy when bubbled through
What is incomplete combustion
A combustion reaction where there is a limited supply of oxygen so water, CO and C (soot) are all produced
Why does incomplete combustion happen
When there isn’t enough O2, the C atoms can’t all form CO2 if there isn’t enough oxygen so they are either made into CO or just C
What are 2 problems of using incomplete combustion
It creates soot and CO
Why is CO a problem
It is a toxic gas, bind to Haemoglobin limiting oxygen supply
Why might cracking be used
If a certain fraction is in high demand but not a lot is produced by distillation
As well as a different hydrocarbon, what else does cracking produce
Hydrocarbons with C=C bonds that are used to make polymers
How does cracking happen?
The crude oil fraction is evaporated and passed over a catalyst containing aluminium oxide and heated to about 650C
What is cracking
Breaking larger alkanes to make a smaller alkane and an alkene
What are 3 benefits of using hydrogen as fuel
It releases a lot of energy
It only produces water vapour
It is easy to ignite
What is a negative of using hydrogen as a fuel
It is a gas at room temp so difficult to store
How is acid rain formed
Sulphur dioxide is an impurity from hydrocarbon fuels
Sulphur dioxide dissolved in water in the clouds to form a mixture of acids, including sulphurous acid (H2SO3)
This is oxidised by oxygen in the air to form sulphuric acid (H2SO4)
What is a problem of acid rain
It corrodes metals like iron
What reaction take solace in a car engine
Internal combustion
What is internal combustion
When fuel is mixed with air and ignited inside the engine
Why is oxides it nitrogen harmful
It makes acid rain, causes pollution, produces a toxic gas
What are oxides of nitrogen produced from
The reaction inside an engine
What was the earths early atmosphere mainly made of
CO2, some water vapour
What helped to form the atmosphere
Volcanic activity
What supports the idea that our atmosphere used to be mainly CO2
Venus and Mars are
What is evidence for the earths atmosphere to mainly be nitrogen?
Titan and a moon of Saturn is
What formed the oceans
4 billion years ago, the earth cooled which cause water vapour to become liquid
True/false, there was a lot of oxygen in our early atmosphere
False
Where was oxygen mainly found
Often found in ancient rock
What evidence supports that there wasn’t much oxygen?
A rock called iron pyrite only forms if there isn’t oxygen
What does rocks containing bands of iron oxide show
There was more oxygen
What do scientists think happened to the CO2 in terms of oceans
It dissolved in the oceans when they were formed
Sea creatures used it to form shells made of calcium carbonate
What are stromatolites
Rocky shapes caused by the build up of sediment and mucus by Cyanobacteria
How much O2 is there in the atmosphere
20%
What is the greenhouse effect
When gases in the atmosphere absorb energy from the sun and re-emit it to the earth and warms it
Give 3 greenhouse gases
CO2, methane and water vapour
What supports the idea that CO2 causes temperature rise?
Satellite data confirms that as CO2 levels increase, there has been a reduction in infrared waves leaving the earth
How can historical evidence be obtained for CO2 levels
Using ice cores and measuring concentration of gas
What equipment is used today to find temperature
Modern thermometers
What greenhouse gas is more powerful that CO2
Methane
When is methane released
When extracting oil and natural gas from the ground and processesd
Besides oil extraction, what also produces methane (2)
Cattle farming as they have bacteria in their stomachs which produce methane
Soil bacteria in landfill sites
Give 5 effects of climate change
Sea level rise Animals moving from natural habitats Species becoming extinct More extreme weather Sea organisms harmed due to acid
What can reduce climate change
Using renewable energy resources
Give a negative of global engineering solutions
So,e countries may not help
What are global engineering solutions
When sunlight is reflected back into space or capture CO2 and bury in underground
Give a way of limiting the impact of the effects of climate change
Helping local people adapt to new conditions e.g building flood defences
