Presentation on theme: "Properties of the Elements The Periodic Table continued…"— Presentation transcript:
Properties of the Elements The Periodic Table continued…
The Elements of the Periodic Table Elements (matter composed of only ONE KIND OF ATOM) can be divided into THREE CLASSES based on their properties: – METAL – NON-METALS – METALLOIDS (Semi-Metals)
METALS Metals are a class of elements having these properties: Luster (shiny surface) Ductile (can be stretched into a thin wire) Malleable ( can be hammered into thin sheets) Good Conductors ( allow heat and electricity to flow through them) Generally have 1 to 4 VALENCE ELECTRONS -(most have 1 or 2)
Reactivity of Metals Metals will react with other elements (usually non-metals) to form compounds. – The metals in Groups 1 and 2 are very reactive. – Group 1 and 2 metals are never found in their PURE FORM in nature…they are in compounds with other elements. Pure Metals must be obtained by chemically separating compounds.
Group 1 ALKALI METALS The Group 1 Alkali Metals are very reactive with water: – Usually stored under kerosene or other oils to prevent contact with water. ALKALI METALS VIDEO Some common uses: Lithium – batteries and medications Sodium – in salts of many kinds and water regualtion in living things. Potassium – in salts, also important for muscle function including the heart.
Group 2 Alkaline Earth Metals The Alkaline Earth Metals are also very reactive, though not as much so as Group 1. – Not found in PURE FORM in nature. – Pure Metal is obtained by chemically separating compounds. Some common uses: Calcium – bones and salts Magnesium – salts and metabolism Barium – X-rays of the digestive system Radium – Radioactive – used in cancer treatment
Groups 3-12 Transition Metals The Transition Metals Group consists of 38 elements. As with all metals, they ductile, malleable, and are conductors. Many of these elements form very brightly colored compound with other elements and are used as paint pigments. Three noteworthy elements are iron, cobalt, and nickel, these are the only elements known to produce a magnetic field.
Some transition elements and their compounds used as pigments:
Group 13 The Boron Family The Boron Family consists of 5 elements. Boron is considered a METALLOID while the rest are considered metals, though they are POOR CONDUCTORS. Some important elements in the group: Boron – used in detergents. Aluminum – many uses. Gallium – a silvery metal that will “melt in your hand!”
Group 14 The Carbon Family The Carbon group consists of 5 elements. The group contains METALS, METALLOIDS and NON- METALS! Some important members of the group: Carbon – basis of life on earth (organic chemistry) Silicon/Germanium– used to make computer chips. Tin/Lead – metals known and used for centuries! – Lead can cause serious damage to the nervous system.
Group 15 The Nitrogen Group This group is made up of 5 elements. This group also contains a NON-METAL, METALLOIDS and one METAL. Some characteristics of the group: Nitrogen – makes up about 78% of the air. Phosphorus – used to make many products from matches, to soaps to plastics. Arsenic – used to make poison! Bismuth – used to make Pepto-Bismol!
Group 16 The Oxygen Family The group consists of 5 elements. Contains NON-METALS, METALLOIDS and a METAL. Some important elements: Oxygen – needed for living things to carry on respiration (release of energy from glucose). Sulfur – an important element in proteins. Polonium – a rare radioactive metal.
Group 17 The Halogen Family The group contains 5 NON-METALS. The name halogen means “salt-forming”. All THREE STATES OF MATTER are found in the family: Fluorine and Chlorine – gases Fluorine – healthy teeth and refrigerants Chlorine – disinfectant and table salt (sodium chloride) Bromine – one of only 2 liquid elements (what is the other one??) - used as an industrial solvent. Iodine - a solid element essential for proper THYROID function.
Group 18 The Noble Gas Family Contain 6 ODORLESS, COLORLESS gases that DO NOT REACT easily with other elements. Common members of the family: Helium – a carrier gas. Neon – lights and medical lasers. Radon – odorless, colorless, RADIOACTIVE gas. – 2 nd leading cause of LUNG CANCER.