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

1.       Saturated hydrocarbons are called alkanes

2.       Small chain hydrocarbons are used as fuels

3.       The reaction is called combustion

4.       The word equation for  this chemical reaction is :

fuel (hydrocarbon) + oxygen → carbon dioxide + water + ENERGY (heat, light, sound)

5.       If there is insufficient oxygen then the word equation is:

fuel (hydrocarbon) + oxygen → carbon monoxide + water + ENERGY (heat, light, sound)

6.       The problem with this reaction is that carbon monoxide is produced this gas is a poison to the human body (see objective 5.11)

7.       Where can you find incomplete combustion? in car engines

8.       What is used to reduce the harmful products from incomplete combustion? catalytic converter

9.       During incomplete combustion a smoky flame is often seen, explain this observation. solid carbon that has not reacted

Extn: write a balanced equation (with state symbols) for the combustion of propane gas

C₃H₈ + 5O₂ ---> 3CO₂ + 4H₂0

3.2 and 3.3 I can recall the general formula and displayed formulae of alkanes

What is the general formula for alkanes?      CnH2n+2
Describe and explain the trend in boiling point: A straight-chain alkane will have a boiling point higher than a branched-chain alkane due to the greater surface area in contact and the mass of the alkane increase the boiling point increases

Draw the displayed formula of the three isomers of pentane:

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

Term	Definition	Example
Homologous series	having the same functional group but differing in composition by a fixed group of atoms	alkane
Hydrocarbon	Compound of hydrogen and carbon	Alkenes, alkanes
Saturated hydrocarbon	Have single bonds	alkanes
Unsaturated hydrocarbon	Have double and/or   single bonds	alkenes
General formula	Series it shows the relationship between the number of C atoms and H atoms in the compounds	for Alkanes it is CnH2n+2 for alkene it is CnH2
Isomerism	compounds with the same formula but a different arrangement of atoms in the molecule and different properties	2,2dimethylpropane

5.13 I can describe catalytic cracking of long-chain hydrocarbons

1) define the word catalyst: a substance that changes the rate of reaction
2) why is catalyst used? to speed up the reaction rate of cracking, they can also slow down reactions such as for rusting
3) why are high temperatures needed?high temps are needed to break the strong covalent bonds in the hydrocarbon 



What types of catalysts are used for cracking? silica and alumina
What equipment do you need to collect the gas? boiling tube, a basin full of water, delivery tube.
What hydrocarbon is he cracking? paraffin
How are alkanes tuned into alkenes? through cracking with either silica or alumina as the catalyst
At what temperature can this experiment work at? 600-700 degrees celsius

5.12 I can recall the problems associated with fractional distillation of crude oil

Read chemistry for you page 145

a) when crude oil undergoes fractional distillation there are too many long chain hydrocarbons (eg bitumen     ) produced and not enough shorter chain hydrocarbons (eg refinery gases)
b) to solve these problems the large chain hydrocarbons undergo a chemical reaction called cracking.

5.11 I can recall how nitrogen oxides are formed in car engines

a.       Write the general equation for the combustion of a fuel : fuel + oxygen -----> energy + oxides

b.      During combustion the nitrogen in air can react to form what gases? NOx gases

c.       What condition is necessary for the formation of these gases? high temperature

d.      In what common object is this condition found? in cars

e.      Why is this condition needed for nitrogen to react? they nitrogen molecules are diatomic and have triple covalent bonds 

f.        What are the dangers of the products from this reaction? asthma, cancers, acid rain

5.7 how is crude oil separated

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

What are the properties of carbon monoxide? Clear, odorless gas, cant see it, highly poisonous

Explain how carbon monoxide is formed? Through incomplete combustion when there is insufficient oxygen

Explain why carbon monoxide is poisonous? it binds very strongly to hemoglobin, when it attaches, it is very difficult to release, when you breath in carbon monoxide, it sticks to your hemoglobin and takes up the oxygen binding sites. and your blood loses ability to transport oxygen, and you suffocate.

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

a.       What is the trend in boiling point of the fractions?        as you go lower the fractions the boiling point gets higher             

b.      Define viscosity      the thickness of a liquid       

c.      What is the trend in viscosity of the fractions?   higher viscosity towards the bottom of the fractionating column 
      What is the trend in colour of the fractions?        colour gets darker when fractions have a higher viscosity

e.      Why is crude oil separated into fractions?      Crude oil on its own its useless, when extracted it has lots of uses

f.        What process is used to separate crude oil into fractions? Fractional distillation

g.       What physical property allows this process to work? each fraction has  adifferent boiling point

5.8 I can recall the names and uses of the main fractions obtained from crude oil

f