Structure of the earth:
The Earth's Lithosphere is relatively cold and rigid. It is the outer part of the earth made up of the crust and the top of the mantle.
in 1912 Alfred Wegener suggested that millions of years ago all of the continents were joined together because the continents look like they would fit together like a jigsaw and similar animal species can be found on either side of the atlantic.
Volcanos can produce two types of lava:
Iron-rich basalt lava is runny and has safe eruptions where as...
Silica-rich rhyolite is thicker and results in more violent eruptions, Rhyolite creates pumice, volcanic ash and bombs.
Rocks differ in hardness because of how they were made:
Limestone is sedimentary rock,
Marble is metamorphic, formed by limestone put uner pressure and heated making it harder,
Granite is igneous rock.
Limestone and marble are made of calcium carbonate, when calcium carbonate is heated it brekas down into calcium oxide and carbon dioxide.
Calcium Carbonate--->Calcium oxide + Carbon Dioxide
CaCo3(s) ---> Cao(s) + Co2(g)
A composite material combines the best properties of each component material, reinforced concrete combines the strength and flexibility of steel bars with the hardness of concrete, create much more uses than ordinary concrete.
Mines and Quarries can be:
be noisy and dusty
take up land
increase local traffic.
Metals and Alloys:
Copper is extracted from copper ore by heating it with carbon
Copper Oxide+Carbon--->Copper+Carbon Dioxide
2CuO(s) + C(s) ---> 2CuO(s) + Co2(g)
Copper is an expensive process, it is cheaper to recycle copper than to extract it from its Ore, however if Copper is mixed with other metals it can be purified using electrolysis..
Electrolysis uses an electric current to break down compounds into simpler substances.
Electricity is passed through a liquid solution called an electrolyte eg copper sulphate solution, to make simpler substances.
Electrodes are used to allow electricity to flow through the electrolyte:
the anode (positive electrode) is impure copper
Cu - 2e- ---> Cu2+
the cathode (negative electode) is pure copper
Cu2+ + 2e- ---> Cu
An Alloy is a mixture of a metal and another element, usually another metal.
Alloys improve the properties of the metal and make them more useful, often harder and stronger than the pure metal.
Amalgam, made from mercury, is used for fillings in teeth
Solder,made from lead and tin, is used to join wires
Brass,made from copper and zinc, is used in door handles,coins, and musical instruments
A smart Alloy such as nitinol, nickel and titanium, can be bent and twisted but will then return to its original shape when heated because it has shape memory, often used in reading glasses frames.
Materials in a car:
Different Materials are used in a car such as:
Nylon Fibre in seatbelts to make…