Carbon compounds and fuels and feedstocks GapFill

The raw material for many organic compounds is  crude oilcarbonate lubricantcoarse sandviscous nitratephosphate rocknitrocarbon, which was formed over millions of years, mainly from the remains of  planktonshellsquartzbonesrocksleaves buried in mud. It is made up of mixtures of hydrocarbons, which contain alkanes with different length chains. The hydrocarbons can be separated into fractions using  chromatographytitrationfractional distillationfractional combustionfiltrationelectrolysis.

Different fractions have different uses, including solvents, lubricants, making polymers and  natural materialspigmentsfuelscosmeticshigh-protein foodelectronics. When separating the fractions, crude oil enters the column at the bottom and then  evaporatessolidifiescrystallisesliquefiescongealscondenses. Higher in the column, the temperature is  highermore changeablemore constantconstantly increasinglowerfluctuating, so different fractions condense at different heights in the column, depending on their  boiling pointfreezing pointmelting pointentropyenergy contentviscosity.

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  usefulefficientviscousflammableexpensivesaturated and less  cheapthermally conductiveflammabledenseunsaturatedpungent. Alkanes are often used as fuels, which involves a  slowcondensationreductionpolymerisationcombustionfermentation reaction, which releases energy. The alkane reacts with oxygen to form  hydrogen chloridecarbon dioxidemethanesulfuric acidcarbon monoxideenergy and water.

Longer alkanes are often  pressuriseddistilledcrackedburnedcondensedmelted, forming shorter alkanes and  alkenesbasesalcoholsmetalswatercarboxylic acids. There are two kinds of cracking:

•  volatile crackingexplosive crackingpressure crackingsteam crackingincendiary crackingchamber cracking, where a high temperature and pressure are used
•  hydrocarbon crackingenzymatic crackingcarbocation crackingcombustion crackingcatalytic crackingactivation cracking, which uses a high-temperature catalyst