C1.5 Fuels Flashcards
(43 cards)
What is fractional distillation?
Separating crude oil into different length hydrocarbons.
What is crude oil?
A mixture of different length hydrocarbons that is found in the ground. It is a fossil fuel.
What is a fraction?
A fraction contains hydrocarbons of similar length that have one function.
What are the order of fractions starting with the shortest chain hydrocarbon?
Gases Petrol Naphtha Kerosene Diesel Fuel oil Bitumen
What are sone properties if short chain hydrocarbons?
More flammable
Less viscous
What is complete combustion?
When hydrocarbons burn with enough oxygen, to produce only carbon dioxide.
What is the word equation for complete combustion?
Hydrocarbon + Oxygen -> Carbon dioxide + Water
What is incomplete combustion?
When hydrocarbons burn without enough oxygen to produce carbon, carbon monoxide, carbon dioxide and water.
What is the word equation for incomplete combustion?
Hydrocarbon + oxygen -> Carbon + Carbon monoxide + Carbon dioxide + Water
Why is incomplete combustion a problem?
It produces toxic carbon monoxide - which is colourless, odourless and extremely toxic.
What factors should you consider when choosing a fuel?
Ease of ignition
Energy value
Ash and smoke produced
Storage and transport ease.
Why can burning fossil fuels be a greater problem for the environment?
They contain sulphur impurities. This is released into the air as sulphur dioxide.
Why is sulphur dioxide in the air a problem?
It combines with clean clouds to form acid clouds which rain acid rain.
What are the problems caused by acid rain?
It causes lakes to become acidic which kills the animals and plants
It kills trees
It destroys limestone buildings and statues.
What can be done about the sulphur impurities in fuels?
It can be removed in the fuel before it is burnt - but this is expensive, uses energy and makes the fuel lose energy
Power stations use acid gas scrubbers to remove harmful gases before they release their emissions
Cars have catalytic converters.
Why are greenhouse gases bad in too high concentrations in the atmosphere?
They act as an insulating layer and radiate heat from the sun back to earth rather than letting it escape.
How does human activity affect Carbon dioxide levels?
When we burn things, we release ‘locked up’ carbon dioxide back into the atmosphere.
What is iron seeding?
When iron is injected into the ocean to encourage photosynthesis and the growth h of phytoplankton. They absorb carbon dioxide from the atmosphere.
What are the problems with iron seeding?
Some plankton may be toxic and grow in large numbers
Dead zones are created in the ocean where nothing can live as the microorganisms that decompose the plankton use up all the oxygen.
What is another way that carbon dioxide can be removed from the atmosphere?
Scientists are researching if waste carbon dioxide can be turned into more useful hydrocarbons. This would only work if the energy used for this process was green energy.
What are the two main types of biofuels?
Biogas
Ethanol
What is biogas?
Biogas is a gas created by microorganisms when they decompose living organisms waste or dead plants.
What are the uses of biogas?
It can be burned to heat water for central heating systems.
It can power a turbine ti produce electricity
It can also be a fuel for cars and buses
What are the advantages of biogas?
It is renewable
It is carbon neutral
It is fairly clean and has very few sulphur impurities or produce oxides of nitrogen
The raw materials are very cheap.
