Chemistry: Chemicals from Oil

Covalent substances

1.37 describe the formation of a covalent bond by the sharing of a pair of electrons between two atoms

1.38 understand covalent bonding as a strong attraction between the bonding pair of electrons and the nuclei of the atoms involved in the bond

1.39 explain, using dot and cross diagrams, the formation of covalent compounds by electron sharing for the following substances:

1. hydrogen

2. chlorine

3. hydrogen chloride

4. water

5. methane

6. ammonia

7. oxygen

8. nitrogen

9. carbon dioxide

10. ethane

11. ethene

1.40 recall that substances with simple molecular structures are gases or liquids, or solids with low melting points

1.41 explain why substances with simple molecular structures have low melting points in terms of the relatively weak forces between the molecules

1.42 explain the high melting points of substances with giant covalent structures in terms of the breaking of many strong covalent bonds

1.43 draw simple diagrams representing the positions of the atoms in diamond and graphite

1.44 explain how the uses of diamond and graphite depend on their structures, limited to graphite as a lubricant and diamond in cutting.

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3.1 explain the terms homologous series, hydrocarbon, saturated, unsaturated, general formula and isomerism.

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3.2 recall that alkanes have the general formula C_nH_2n+2

3.3 draw displayed formulae for alkanes with up to five carbon atoms in a molecule, and name the straight-chain isomers

3.4 recall the products of the complete and incomplete combustion of alkanes

3.5 recall the reaction of methane with bromine to form bromomethane in the presence of UV light.

3.6 recall that alkenes have the general formula C_nH_2n

3.7 draw displayed formulae for alkenes with up to four carbon atoms in a molecule, and name the straight-chain isomers

3.8 describe the addition reaction of alkenes with bromine, including the decolourising of bromine water as a test for alkenes.

3.12 describe the dehydration of ethanol to ethene, using aluminium oxide.

5.6 recall that crude oil is a mixture of hydrocarbons

5.7 describe how the industrial process of fractional distillation separates crude oil into fractions

5.8 recall the names and uses of the main fractions obtained from crude oil: refinery gases, gasoline, kerosene, diesel, fuel oil and bitumen

5.9 describe the trend in boiling point and viscosity of the main fractions

5.10 recall that incomplete combustion of fuels may produce carbon monoxide and explain that carbon monoxide is poisonous because it reduces the capacity of the blood to carry oxygen

5.11 recall that, in car engines, the temperature reached is high enough to allow nitrogen and oxygen from air to react, forming nitrogen oxides

5.12 recall that fractional distillation of crude oil produces more long-chain hydrocarbons than can be used directly and fewer short-chain hydrocarbons than required

5.13 describe how long-chain alkanes are converted to alkenes and shorter-chain alkanes by catalytic cracking, using silica or alumina as the catalyst and a temperature in the range of 600?700?C.

5.14 recall that an addition polymer is formed by joining up many small molecules called monomers

5.15 draw the repeat unit of addition polymers, including poly(ethene), poly(propene) and poly(chloroethene)

5.16 deduce the structure of a monomer from the repeat unit of an addition polymer

5.17 recall that nylon is a condensation polymer

5.18 understand that the formation of a condensation polymer is accompanied by the release of a small molecule such as water or hydrogen chloride

5.19 recall the types of monomers used in the manufacture of nylon

5.20 draw the structure of nylon in block diagram format.

Source: http://intranet.wellingtoncollege.org.uk/chemistry/new-igcse/chemicals-from-oil

st. nicholas st. nicholas heisman finalists heisman finalists kepler 22 b kepler 22 b rosie o donnell