C1B edexcel

Air is made up of:                                                                                           

78% Nitrogen (boils at -196 degrees)                                                                

21% Oxygen (boils at -187 degrees)                                                                  

1% mainly Argon                       

Can seperate gases in the air through fractional distillation depending on the different boiling points. Nitrogen boils of first.

Uses                                                                                                          

Oxygen: Wielding, Rocket Engines and Hospitals                        

Nitrogen: Making Ammonia (fertilisers), creating unreactive atmosphere, Drilling Crude Oil and keeping things cold (liquid)

Salt (Sodium Chloride) can electrolyse to produce Hydrogen, Chlorine + Sodium Hydroxide. Sodium can be extracted from electrolysis from molten Sodium Chloride.

Uses                                                                                                       

Chlorine: Bleach, steralising water, making Hydrochloric acid, insecticides, plastics, pesticides and weedkillers                                                                                     

Hydrogen: Making Ammonia, Margerine, Fuel, Wielding and Metal Cutting            

Sodium: Detergent, extracting titanium and coolant in nucleur reactors                 

Sodium Hydroxide (Strong Alkali): Soaps, Ceramics, extracting Aluminium, paper pulp, oven cleaner and bleach

Crude oil is a mixture of mainly hydrocarbons which consists of carbon + Hydrogen. Crude oil is put in at the bottom of the fractionating column. Large molecules condense first.                

Small molecules, Low boiling point, Light in colour, easy to light, Runny (viscous)                  

Lord: LPG (liquefied Petroleum gas)- Bottled gas

Peter: Petrol- Fuel for cars

Nailed: Naphtha- Chemicals:  for plastics, dyes, drugs, explosives, paints…

Kate: Kerosene (paraffin) - Jet Engines, lighting and heating

Daphne: Diesel- Fuel

On: Oil (Lube) –lubricating oil, waxes, polishes + (Fuel) –ships, factories, central heating

Bitumen (rd): Roads and Roofing                    Opposite: (large molecules)

Complete combustion happens when there's plenty of oxygen. This process releases a lot of energy and only two harmless products (CO2 + H2O). When this happens the gas burns with a clean blue flame. Hydrocarbons include:       Methane (CH4), Butane (C4H10), and Methanol (CH3OH).

Incomplete combustion occurs when there's not enough oxygen for the hydrocarbon to fully burn. This produces a smoky yellow flame which produces less energy. Additionally, 2 other harmful products are formed: Carbon & Carbon Monoxide.

Carbon Monoxide is a colourless, odourless, toxic and poisonous gas which is why many people die as it cannot be detected. This can be caused by faulty gas boilers and fires which is why regular checks are important. The black carbon gives off soot which shows that it's not burning properly. 

You can use this formula to get the balanced equation:

C=x                                                                                        

H= 2x+2

Best fuel depends on considering:

Energy Value: The amount of energy released

Pollution: Whether this will add to acid rain + greenhouse effect and the sootiness of the flame

Residue: Some fuels like coal leave behind a lot of ash that needs to be disposed 

Ease of use: Whether it ignites (catches on fire) easily + whether you can move it easily

When fossil fuels burn they release mainly CO2 but other harmful gases like sulphur dioxide and nitrogen oxides are produced. When these gases mix with the clouds, the products fall as acid rain. Acid rain + pollutants are blamed for the increasing number of asthma cases. 

Carbon Monoxide can stop your blood carrying oxygen around the body. It combines irreversibly with haemoglobin in the blood cells, decreasing the space for the oxygen. A lack of oxygen can cause fainting, coma, or even death.

Photochemical smog is caused by sunlight acting on the nitrogen oxides and other pollutants. These oxides form the ozone (O3). Ozone can cause breathing difficulties, headaches and tiredness. There's a clear correlation between the number of deaths and the amount of pollution which shows that death is caused by pollution.

The greenhouse gases trap the heat radiation and the two main gases are methane and CO2. These are released as part of our everyday life. As we become more industrialised, more CO2 are released. Scientists have 2 theories: Earth is gradually warming + fossil fuel use has got something to do with it.

Computer models: are fast, used to predict the temperature of Earth's atmosphere in the future. Computer models are only good as the data you put in them. If any of it is wrong the whole prediction will be affected.

Precautionary Principle: Burn less fossil fuels: burn more sufficiently + use other energy sources. Burn fossil fuels but stop the levels of greenhouse gases increasing: capture the CO2 before it's released into the atmosphere + plant more forests so the gas is absorbed.

Recycling                                                                                                                  Use fewer resources: conserves the resources as there are limited materials in Earth, Use less energy: Recycling doesn't use a lot of energy, Use less money: saves money as energy doesn't come cheap and make less rubbish: cuts down the amount of junk going into the lanfill sites.

Hydrogen Gas: Use to power vehicles, fuel cells make electrcity from hydrogen and the oxygen in the air. Hydrogen can be extracted from water but it takes electrical energy to extract it. Fuel cells don't produce harmful products. However, it's expensive and isn't widely available. It's also hard to store and explosive.

Biofuels are alternatives for fossil fuels: Renewable resources. Made up of living organisms' waste or dead plants. Microbes are used to decompose the waste + plants to create biogas for fuel, also can be used to power turbine or generate electricity. Plants grown to make biogas can photosynthesise to remove CO2. Doesn't produce polution, cheap and readily available. However, large amounts of land needed to grow crops.

Alcohol can be used for fuel. Ethanol: burns to give ONLY CO2 and H2O, can be produced using yeast to ferment sugars. Cars: can be run to adapt 10% of ethanol + 90% petrol- "gasohol". Using gasohol instead of pure petrol means less crude oil is used. Crops needed to grow ethanol absorbs CO2 which balances the release of CO2 when it's burned. But distilling the ethanol after it is fermented takes a lot of energy so it is not a perfect solution.