Carbon compounds and fuels and feedstocks GapFill

The raw material for many organic compounds is  coarse sandcarbonate lubricantnitrocarbonphosphate rockcrude oilviscous nitrate, which was formed over millions of years, mainly from the remains of  planktonrocksquartzleavesbonesshells 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  titrationfiltrationfractional combustionchromatographyelectrolysisfractional distillation.

Different fractions have different uses, including solvents, lubricants, making polymers and  high-protein foodelectronicsnatural materialscosmeticsfuelspigments. When separating the fractions, crude oil enters the column at the bottom and then  liquefiescondensessolidifiescongealsevaporatescrystallises. Higher in the column, the temperature is  fluctuatingmore changeableconstantly increasinghighermore constantlower, so different fractions condense at different heights in the column, depending on their  melting pointviscosityenergy contententropyboiling pointfreezing point.

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  efficientsaturatedusefulexpensiveflammableviscous and less  cheapunsaturateddensethermally conductivepungentflammable. Alkanes are often used as fuels, which involves a  reductioncombustionslowpolymerisationcondensationfermentation reaction, which releases energy. The alkane reacts with oxygen to form  carbon monoxidemethanecarbon dioxideenergyhydrogen chloridesulfuric acid and water.

Longer alkanes are often  condensedcrackedmeltedpressurisedburneddistilled, forming shorter alkanes and  metalscarboxylic acidsalkenesalcoholsbaseswater. There are two kinds of cracking:

•  explosive crackingchamber crackingvolatile crackingsteam crackingincendiary crackingpressure cracking, where a high temperature and pressure are used
•  catalytic crackingcombustion crackinghydrocarbon crackingactivation crackingcarbocation crackingenzymatic cracking, which uses a high-temperature catalyst