3How coal formedMillions of years ago trees died and fell to the bottom of swamps.Over time they became covered by mud and rock.…the trees became fossilized, forming coal.Over millions of years, due to high temperatures and pressure…
5Hydrocarbons are molecules that contain carbon and hydrogen only. Crude oilCrude oil is a mixture.It contains hundreds of different compounds. Some are small but most are large.Nearly all of these compounds contain carbon and hydrogen only.They are called hydrocarbons.Also some other compounds contain small amounts of N and S. Why?Hydrocarbons are molecules that contain carbon and hydrogen only.
6How oil and natural gas formed Q1 Explain why oil contains carbon and hydrogen.Q2 Explain where the energy in oil originated.
7The importance of oilThe hydrocarbons in crude oil are essential to our way of lifeWe use them as fuels for most forms of transport.We also use them as raw materials from which a HUGE range of useful everyday substances are made .. Such as…………..make a list!
8Making oil usefulCrude oil is a mixture of hydrocarbons with a VERY wide range of sizes.Crude oil itself has no uses because its properties arenot definite.To make crude oil into useful substances we have to separate the mixture into molecules of similar size.This is done in an oil refinery in a process called fractional distillation.The physical property used to separate the fractions is boiling point.
10Fractional Distillation Can you predict and explain where the fractions are obtained from the fractionating tower?coolhotFuel gasPetroleumFractionBoiling Range(oC)KeroseneDiesel220 – 275PetrolBitumen>350Fuel gasBelow 40Lubricating oilKeroseneDieselLub. OilBitumen
11Fractional Distillation Why do these fractions condense over a boiling range?coolhotFuel gasFractionBoiling Range (oC)Fuel gasBelow 40PetrolKeroseneDiesel220 – 275Lubricating oilBitumen>350PetroleumKeroseneDieselLub. OilBitumen
12Uses of each fraction Fuel gas Petrol / gasoline Naphtha Paraffin / Burned in the refinery to fuel the distillation process, sold as LPG, purified and sold as bottled camping gasFuel gasPetrol/ gasolineFuel for cars and motorcycles, also used to make chemicals.NaphthaUsed to make chemicals used everwhere.Paraffin /KerosineFuel for greenhouse heaters and jet engines, manufacture of chemicals.Diesel fuelFuel for lorries, trains.Fuel andlubricatingoilFuel for the heating systems of large buildings, fuel for ships, lubricating oil.BitumenRoofing, and road surfaces.
14Similarities between crude oil and its fractions: Differences between crude oil and its fractions:
15The boiling points of molecules In general, the bigger the molecule the higher the boiling point.No. Carbon atoms B.Pt(oC)
16Fraction Boiling Range (oC) Number of carbons 1-5 5-10 9-14 13-17 Here are the boiling ranges of some fractions obtained from distillation of petroleum.Using the previous graph, estimate the size range of the molecules present in each fraction.FractionBoiling Range(oC)Number of carbonsFuel gasBelow 40PetrolKerosineDiesel1-55-109-1413-17
17What is crude oil?Crude oil is a mixture of different sized hydrocarbons. The exact composition depends upon where the oil comes from but typically it contains a lot of big molecules. (Why is this not good?)Small moleculesBig moleculesMedium molecules
18Which is a correct statement about crude oil? A mixture of carbohydrates.Formed by the decay of dead sea creatures.Consist of a mixture of very large molecules.Is purified in an oil rig.
19Which is a correct statement about fractional distillation?Oil is separated into fractions with the same size molecule.Oil is separated into fractions with the same density.Oil is separated into fractions with similar size molecules.Oil is separated into alkanes and alkenes.
20Which is a correct order for these fractions working down from the top of the column? Fuel gas, kerosene, petrol, diesel, bitumen.Fuel gas, diesel, kerosene, petrol, bitumen.Fuel gas, petrol, diesel, kerosene, bitumen.Fuel gas, petrol, kerosene, diesel, bitumen.