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Organizing the Elements Class Notes An element’s properties can be predicted from its location in the periodic table. METALS: 5 Physical properties of Metals: Luster – the shininess of metal or rock All metals except for gold and copper are silver-grey in color. Malleable – when a substance can be hammered or shaped without breaking Ductile – substances that can be drawn into wires Conductors – can carry electrons or electricity usually well and can also transfer heat well Solid- all metals (except for Hg which is a liquid) are solid at room temperature Chemical properties of Metals: Corrosive – metals can be gradually eaten away and changed into some other metal compound like iron oxide or rust Oxides – compounds containing oxygen (ex. Copper turns green, bronze turns brown, silver tarnish is black) Metals in the periodic table of elements are arranged into families with similar but not identical properties. Two special families of metals: Alkali Metals – with the exception of H all elements in Group 1. They are softer and less dense than most metals. Very reactive. (remember the video where K blew up) Alkali Earth Metals – the metals in Group 2. These are harder and denser than the alkali metals. Less reactive. TRANSITION METALS: These are elements that fall in the middle of the periodic table. These thirty elements are all metals and are all called transitional. They are hard, brittle and have high melting points. Many compounds containing these metals are very colorful. Alloys – a mixture of two or more elements having the properties of metals. RARE EARTH METALS: Lanthanides. NONMETALS: Nonmetals are solids, gases and include one liquid (Br). They are difficult to distinguish and vary in color, too. Solid nonmetals are brittle and break easily. Nonmetals are not malleable, shiny or ductile and do not conduct heat or electricity very well. Chemical properties of Nonmetals: Metals have a tendency to give away the electrons in their outer shells. Nonmetals however, usually attract electrons. Nonmetals have a tendency to react with metals. Two special families of nonmetals: Halogens – combine readily with metals and form salts. A salt is a compound in which a metal is combined with one or more nonmetals. Noble Gases – are said to be inert. Group 18. This means they do not readily mix with other elements, Their outer electron shells are full and therefore stable. This makes it difficult for them to bond with other elements. METALLOIDS (Poor Metals, Other Metals): These have properties between metals and nonmetals. Two special metalloids are: 1) Boron – it will conduct electricity at high temperatures unlike most metals 2) Silicon – this is the most abundant element in the Earth’s crust. It is used in many industries.