Alkane 12

Question 1

Polarity

Answer 1

Non-polar

Weak intermolecular forces between molecules are weak van der walls forces

Question 2

Boiling point

Answer 2

Boiling point increases when the chain increases, shorter chains are gases at room temperature

Solid when over 18 carbons

Question 3

Solubility

Answer 3

Insoluble in water because water molecules are bonded by hydrogen bonding

Question 4

How alkanes react

Answer 4

Relativity unreactive

Can burn and react with halogens under suitable conditions ( a plentiful oxygen supply)

Question 5

Fractional distillation of crude oil

Answer 5

Crude oil is first heated in a furnace
Mixture of liquid and vapour passes into a tower that is cooler at the top
Vapours pass up the tower via a series of trays
Condense to liquid
Liquid is pumped off

Question 6

Bitumen

Answer 6

Road surfacing

Question 7

Gasoline or petrol

Answer 7

Cars

Question 8

Kerosene or paraffin

Answer 8

Jet fuel

Question 9

Diesel oil

Answer 9

Lorries and taxes

Question 10

Lubricating oil and waves

Answer 10

Candles and engine oil

Question 11

Fuel oil

Answer 11

Ships

Power stations

Question 12

Fracking

Answer 12

Gas can be extracted by drilling ibto the shale and forcing pressuried water mixed with sand. This means that the rock breaks up realesing trapped gas.
Natural gas

CH4 + 2O2 —— 2CO2 + 2H2O

Question 13

Opposition of fracking

Answer 13

Don’t like the infrastructure of wells and the associated traffic
Concerns about the amount of water used
Worried about chemicals added to the water
Can cause small earthquakes
Burning natural gas producing carbon dioxide

Question 14

Thermal cracking

Answer 14

Heating alkane to a high temperature (700-1200K) and high pressure (7000kPa)

Creates free radical to create small chains (free radicals = highly reactive)
(Thermal cracking takes place at high pressure and high temperature and produces a high percentage of alkenes)

Question 15

Catalytic cracking

Answer 15

Temperature of 720K
Lower pressure
Zeolite catalyst ( honeycomb structure with a large surface area)
Acidic
Used to produce motor fuels
(Catalytic cracking takes place at a slight pressure, high temperature and in the presence of a zeolite catalyst and is used mainly to produce motor fuels and aromatic hydrocarbons)

Question 16

Combustion

Answer 16

Burn in a plentiful supply of oxygen
Give out heat ( large negative enthalpies)
More carbon more heat

Question 17

Incomplete combustion

Answer 17

Limited supply of oxygen

Carbon monoxide is produced

Question 18

NO
NO2
N2O4
(Nitrogen oxides)

Answer 18

Can happen when in a petrol engine at high temperature. Oxygen reacts with the water vapour

Question 19

Sulphur dioxide

Answer 19

Acid rain

Sulphur impurity in crude oil

Question 20

Carbon particles

Answer 20

Can exacerbate asthma and cause cancer

Question 21

Unburnt hydrocarbon

Answer 21

Photochemical smog

Question 22

Flue gas desulfurisation

Answer 22

When you burn fossil fuels there are sulphur impurities and sulphur dioxide is produced.

Calcium oxide and water to from calium sulfate which can be oxidised to make gypsum which is used in plaster board.

Or you can use lime stone

Question 23

Catalytic converter

Answer 23

Honeycomb made of ceramic material coated in platinum and rhodium metals

React to form less harmful gases

Question 24

Alkanes

Answer 24

Saturated hydrocarbon

Carbon and hydrogen only

Question 25

Global warming and green house effect

Answer 25

Carbon dioxide behaves like glass, it traps infrared radiation so the earth heats up. Other greenhouse gases such as methane and water vapour.

Question 26

Carbon neutral activities

Answer 26

Actives such as airline flights produce a large amount of carbon dioxide.

Question 27

Process in a Chain reaction

Answer 27

Initiation
Propagation
Termination

Question 28

Initiation

Answer 28

Uv light

Cl2 —- 2Cl.
Two chlorine radicals
Free radicals are highly reactive

Question 29

Propagation

Answer 29

Cl. + CH4 —— HCl + .CH3

.CH3 + Cl2 ——- CH3Cl + Cl.

Both of the equations create another free radical

Question 30

Termination

Answer 30

Cl. + Cl. —– Cl2

.CH3 + .CH3 —— C2H6

Cl. + .CH3 —— CH3Cl

Forms no unpaired electrons

Question 31

Chlorofluorocarbons and ozone layer

Answer 31

Cl. + O3 —- ClO. + O2

ClO. + O3 —– 2O2 + Cl.

2O3 —– 3O2

Question 32

Cracking

Answer 32

Splitting larger hydrocarbon chains into smaller ones which are more useful

Question 33

Why is cracking important?

Answer 33

High market demand for smaller hydrocarbon chains

Larger hydrocarbon chains are split

Question 34

Alkenes and alkanes

Answer 34

Alkenes are more useful than alkanes at starting materials for further chemical reaction

Question 35

Polluting gases

Answer 35

Soot
Water vapour
Carbon dioxide
Carbon monoxide
Unburnt hydrocarbon
Nitrogen oxides
Sulphur dioxide

Question 36

Removing sulfur (flue gas desulfurisation)

Answer 36

Power station
Acid rain

Calcium oxide + water
Calcium sulfite (oxides)
Gypsum (used in builders plaster)

CaO + 2H2O + SO2 + 1/2O2 ——— CaSO4.2H2O
CaCO3 + 1/2O2 + SO2 —— CaSO4 + CO2

Question 37

Catalytic converter

Answer 37

Internal combustion engine
Reduces amount of pollutants ( big surface area)
Honeycomb made of ceramic material coated with platinum and rhodium metals

2CO2 + 2NO —– N2 + 2CO2

Question 38

Global warming

Answer 38

Visible rays from the sun pass through the carbon dioxide ( traps infrared radiation)

Question 39

Halogenalkanes

Answer 39

Only react with UV light

So they don’t react in a dark room

Question 40

Alkanes

Answer 40

Saturated hydrocarbons

Question 41

Incomplete combustion

Answer 41

C3H8 + 7/2O2 —– 3CO2 + 4H2O