CHEMISTY

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Atoms

Proton- 1 (mass) - positive charge - found in Neucleus 

Electron- 0 (mass) - negative charge - found on the shells

Neutron- 1 (mass) - 0 charge - found in the Neucleus 

NE 10  (atomic no. / no. of protons) 

       20.18  (mass no. / proton + neutron) 

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LIMESTONE

Limestone reactions- 

          CaCo3 (heat going in and carbon dioxide going out) - Quicklime (H3O going in and heat going out) - Hydrated lime (Carbon dioxide going in) 

THIS IS CALLED THERMAL DECOMPOSITION

CaCO3 --------------- CaO+Co2

          heats up  

Quarrying-                                            Disadvantages: 

Advantages: 

.better infrastructure                             .Noise and dust

.More jobs                                           .Ruins Landscape

.Stone is cheaper                                 .Traffic Jam

.Economic growth                                 .Habitats destroyed

.Can be used for enterntainment

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EXTRACTING METALS

COPPER- bioleaching, smelting,displacement (more reactive metal)

IRON-blast furnance, carbon removes oxygen from iron (iron is a more reactive metal)

REACTIVE METALS- electrolyisis ( melt it and pass an electric current through) 

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CRUDE OIL

HYDROCARBON- a mixture of hydrogen and carbon atoms only

ALKANE- a saturated hydrocarbon (no double bond)

ALKENE- a unsaturated hydrocarbon (double bond)

Fractional distilation: The crude oil is heated- then evaporates- cools when gets up collumn - different chain lengths - different boiling points - condense at different heights - collect fractions       

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CRACKING

cracking hexane- pass over to a hot catalyst

C10 H22 - C2 H4 + C8 H18 (minus)   makes alkenes 

Cracking makes longer chains into shorter chains, which is more useful.

They can be used to make polymers 

POLYMERISTATION- 

poly=many

Double bond breaks in each unit 

After this, it forms new bonds between the carbon (polyethene) 

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LANDFILL

Landfill - cheap and easy, but its; difficult to find places to put the landfill and polymers are not biogradable

Incineration- can be controlled,very efficient and generates energy.  Produces toxic gases, Carbon Dioxide is formed and increases Green House Gases

Recycling- Less crude oil, Less energy and avoids problems. Time consuming to sort them and expensive

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FERMENTATION AND HYDRATION

Fermentation:                                                                                 

30-40 degrees                                                                              

batch process                                                                                

normal pressure 

slow

renewable raw material

makes impure ethanol (purified by

fractional distilation)

made from sugar,maize or corn

Hydration:

Concentrated phosphoric acid as catalyst

fast

makes pure ethanol

300 degrees

continous process

high pressure 

non-renewable raw materials

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OIL

The oil is obtained from crushed sunflower seeds by pressing

The oil does not dissolve in water

Carbon Carbon double bonds in sunflower oil can be detected by reacting with bromine 

Water is not used to make crisps, but sunflower oil is. This is because sunflower oil has a boiling point of 232 degrees and water has a boing point of 100 degrees. This means that in sunflower oil, the thin potato slices will turn into crisps quicker than in the water. 

Distillation:

The first step of distillation is pressing the plant material to reduce the particle size. The temperature of the steam needs to be carefully controlled- just enough for the plant to produce the essential oil, although it cant be too hot as it would burn. The steam which then contains the essential oil is passed through a cooling system to condense the steam, which forms a liquid, which then the oil and water is seperated.

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EMULSION

An emulsion is a mixture of two immiscible liquids, where tiny droplets of a liquid are mixed evenly through anouther. 

When mixed, the mixture of oil and water will start to separate 

Hydrophic-dissolves in water

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THE EARTH AND IT'S ATMOSPHERE

Alfred's theory:

.Continents had drifted apart, which is called Continentail drift. 

.He pointed out that the fossils in Africa and South America were simular 

.He said that the continents had drifted apart and the animal populations had evolved after that in different ways

.Other scientists claimed that there were land bridges between all the countries to allow the animals to walk across the continent to anouther

The atmosphere:

The earth's atmosphere was like venus', millions of years ago

21 percent- oxyen 

0.9 percent- argon 

0.037 percent carbon dioxide

78 percent nitrogen 

This is the earths atmosphere today


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