CHEMISTRY

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Alloys : Aluminium: The aluminium is important for us because we use it in so many ways for example: - It is very usefull for products that need protection. -It is a good conductor of electricity and heat. -It is a important part of cars,many pieces of cars are made of aluminum. -It is use in buildings. -And it is 100 % recyclable.

The plasctic is very important too for our society because there are many things that we use that are made of it .for example: -containers -parts of games -the outside of computers -the outside of phones -pens Medicine: Blood vessels. Industry: Parts of cars. Sport: Balls.
 * Polymers :Are substances containing a large number of structural units joined. **

resource: [|www.wikipedia.com]

Subatomic Particles: 1.Electron:Electrons have quantum mechanical properties. 2.Neutron:is composed by Dineutrons and tetraneutrons. 3.Proton:Protons are made up of three quarks making them baryons. Vocabulary: Baryons: is a type that is made of three quarks. Down and up quark:are the first-generation quark. Dineutrons:are a hypothetical particle consisting of two neutrons. Tetraneutrons:are a hypothetical particle consisitng of four neutrons. Quantum mechanical:description of all physical systems at the microscopic scale.

The strong interction,or strong force,or color force hold quarks together to form protons,electrons and neutrons.The strong force is the most powerful of the four fundamental forces.

Quarks inside the atom media type="youtube" key="3TEqg_Bd7GE" height="344" width="425"

www.wikipedia.com www.youtube.com

__Helium __  1. Describe the main properties and characteristics of Helium: · Chemical Symbol: He  ·  Origin or meaning: The name comes from the Greek word Helios that means sun. · Helium was discovered by Pierre Jules Cesar Janssen and Sir William Ramsay. · It was discovered in Scotland. · Electronic Configuration:1s2 2. Periodic Properties: ·<span style="font-family: 'Times New Roman'; font-size-adjust: none; font-size: 7pt; font-stretch: normal; font-style: normal; font-variant: normal; font-weight: normal; line-height: normal;"> <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt; line-height: 115%;">Atomic Radius: 31pm ·<span style="font-family: 'Times New Roman'; font-size-adjust: none; font-size: 7pt; font-stretch: normal; font-style: normal; font-variant: normal; font-weight: normal; line-height: normal;"> <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt; line-height: 115%;">Ionization energy: 1st 2372.3kjmol-1, 2nd 0kjmol-1, 3rd kjmol-1. 3.<span style="font-family: 'Times New Roman'; font-size-adjust: none; font-size: 7pt; font-stretch: normal; font-style: normal; font-variant: normal; font-weight: normal; line-height: normal;"> Uses of Helium: <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;"> [|www.wikipedia.com]
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">filling party balloons as it is a much safer gas (non-flammable)
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">widely used as an inert gas shield for arc welding
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">High speeds push gas inside air to air missiles for guidance corrections.
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">protective gas in growing silicon and germanium crystals, and in titanium and zirconium production
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">cooling medium for nuclear reactors, helium won't become radioactive
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">a mixture of 80% helium and 20% oxygen is used as an artificial atmosphere for divers and others working under pressure
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">cryogenics and superconductivity
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">rare document preservation (i.e. Declaration of Independence)
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">as a gas for supersonic wind tunnels
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">pressurizing agent for liquid fuel rockets (inert so won't react)
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">Leak detection agent for extremely small leaks.
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">nuclear detonation simulations (using conventional explosives)
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">isotopic dating by helium ratios (seawater, ocean beds,etc)
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">Helium/neon lasers
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">Helium cardio-pulmonary resusitation pump (heart surgery)
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">Helium filled border patrol "AEROSTAT" monitoring blimps.
 * <span style="font-family: 'Century Gothic','sans-serif'; font-size: 12pt;">Helium filled border patrol "AEROSTAT" monitoring blimps.

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