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Fuels GapFill

Target Level
4-5
Running Total
0
0%
Attempt
1 of 3

You must fill all the gaps before clicking ‘Check Answers!’

The raw material for many organic compounds is  crude oilcoarse sandnitrocarbonphosphate rock, which was formed over millions of years. It is made up of mixtures of hydrocarbons, which contain alkanes with different length chains. The hydrocarbons can be separated into fractions using  filtrationchromatographytitrationfractional distillation.

Different fractions have different uses, including solvents, lubricants, making polymers and fuels or gases. When separating the fractions, crude oil enters the column at the bottom and then  congealscondensesevaporatessolidifies. Higher in the column, the temperature is  higherlowermore changeablemore constant, so different fractions condense at different heights in the column, depending on their  melting pointentropyboiling pointviscosity.

The length of an alkane chain affects the properties of that alkane. For example, a longer alkane will have a higher boiling point, and will be more  saturatedviscousexpensiveuseful and less  densethermally conductiveflammablepungent. Alkanes are often used as fuels, which involves a  combustionpolymerisationfermentationslow reaction, which releases energy. The alkane reacts with oxygen to form  carbon dioxideenergyhydrogen chloridesulfuric acid and water.

Longer alkanes are often  distilledcrackedburnedpressurised, forming shorter alkanes and  metalsbaseswateralkenes

All fossil fuels are non-renewable and contain some amount of  hydrogenheliumsulfurcarbon. This can form a harmful gas which, along with oxides of nitrogen formed in hot engines, is responsible for many respiratory issues in people and the formation of  toxic rainalkali rainpoison rainacid rain, a pollutant which corrodes buildings and damages wildlife. Fossil fuels can also burn incompletely to produce  monoxidescarbon grainssolidatesparticulates, solid particles which can contribute to global dimming, and  xenonnitrogenhydrogencarbon monoxide, a colourless, odourless gas which is toxic to animals.


This is your 1st attempt! You get 3 marks for each one you get right. Good luck!

Pass Mark
72%