CHEMISTY
- Created by: izzy123lvya
- Created on: 24-05-14 15:03
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)
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
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)
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
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)
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
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
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.
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
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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