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Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen

The Periodic Table of Elements 11- 20.


bulletAtomic Symbol: Na
bulletAtomic number:11
bulletAtomic Weight: 22.989770
bulletColour: silvery white
bulletClassification: Metallic

 Sodium in its most common compound is ‘sodium chloride’ (table salt.) Helps regulate blood pressure and water balance in the body  Common salt to human and animal nutrition is integral. Soap is also generally a sodium salt of fatty acids.


bulletAtomic Symbol: Mg
bulletAtomic number:12
bulletAtomic Weight: 24.3050
bulletColour: silvery white
bulletClassification: Metallic

Magnesium is the present in the earth's crust in other elemental forms and is an alkaline earth metals. When magnesium is finely divided magnesium easily ignites upon heat in air and burns with a dazzling white flame. Normally magnesium is coated with a layer of oxide, MgO, that protects magnesium from air and water. Magnesium is a commercially important metal with many uses. Everything from luggage to rockets and planes.



bulletAtomic Symbol: Al
bulletAtomic number:13
bulletAtomic Weight: 26.981538
bulletColour: silvery
bulletClassification: Metallic

Aluminium is a silvery metal that is light, nontoxic (as the metal), nonmagnetic and does not spark. It is easily formed, machined, and cast. Pure aluminium is soft and lacks strength, but alloys with copper, magnesium and silicon to be much stronger and can be used to make many things. Aluminium is found in the earth's crust.



bulletAtomic Symbol: Si
bulletAtomic number:14
bulletAtomic Weight: 28.0855
bulletColour: dark grey/ blue
bulletClassification: Semi – Metallic

Silicon is present in the sun and stars. It is also found in a types of meteorites known as aerolites. Silicon is found largely as silicon oxides such as sand (silica), quartz, rock crystal, amethyst, agate, flint, jasper and opal. Silicon is found also in minerals such as asbestos and clay

Silicon is important in plant and animal life. Silicon is also an important ingredient in steel. Silicon carbide is one of the most important abrasives.



bulletAtomic Symbol: P
bulletAtomic number:15
bulletAtomic Weight: 30.973761
bulletColours: colourless/red/silvery white
bulletClassification: Non-metallic

 Phosphorus is an essential to living systems and is found in nervous tissue, bones and cell protoplasm. Ordinary Phosphorus is a waxy white solid. However when pure, it is colourless and transparent. It catches fire spontaneously in air. When exposed to sunlight, or when heated in its own vapour it is converted to the red variety which does not ignite spontaneously.



bulletAtomic Symbol: S
bulletAtomic number:16
bulletAtomic Weight: 32.065
bulletColour: yellow
bulletClassification: Metallic

Sulfur is also spelt sulphur, but officially it is supposed to be spelt with an ‘f’. Sulfur is a pale yellow, odourless, crumbly solid. Sulfur is essential to life. It is a minor part of fats, body fluids, and skeletal minerals. Sulfur dioxide is a dangerous component in atmospheric air pollution and is one of the factors responsible for acid rain.



bulletAtomic Symbol: Cl
bulletAtomic number:17
bulletAtomic Weight: 35.453
bulletColour: yellowish green
bulletClassification: Non-metallic

 Chlorine is a greenish yellow gas which combines directly with nearly all elements. Chlorine can also cause breathing problems. The gas can irritate the mucous membranes and the liquid can burn the skin. It is not found in a free state in nature.



bulletAtomic Symbol: Ar
bulletAtomic number:18
bulletAtomic Weight: 39.948
bulletColour: colourless
bulletClassification: Non-Metallic

 Argon is colourless and odourless. Argon is very still and is not known to form true chemical compounds. It makes a good atmosphere for working with air-sensitive materials since it is heavier than air.



bulletAtomic Symbol: K
bulletAtomic number:19
bulletAtomic Weight: 39.0983
bulletColour: silvery white
bulletClassification: Metallic

Potassium is an essential constituent for plant growth and it is found in most soils. It is also a vital element in the human diet. It is soft and easily cut with a knife. It is silvery in appearance immediately after a fresh surface is exposed.



bulletAtomic Symbol: Ca
bulletAtomic number:20
bulletAtomic Weight: 40.078
bulletColour: silvery white
bulletClassification: Metallic

Calcium is an essential part of leaves, bones, teeth, and shells.

The metal is a silvery colour and is rather hard. Calcium does not occur free in nature. Calcium is found mostly as limestone, gypsum and fluorite. Stalagmites and stalactites that form in beautiful caves contain calcium carbonate.