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Periodic Table
Chemistry
Term | Definition |
---|---|
Metals | -solid at room temperature , -ductile, -malleable, -high density, - high melting points, -good conductor of heat & electricity, -shiny luster, and has reactivity. |
Non-Metals | -No luster - Poor conductors of heat & electricity - Brittle -not ductile -not malleable -low density -less reactive than metals |
Periodic Table | - arranges ALL of the known elements in order of increasing atomic # (# of protons) - order generally coincides (same) w/ increasing atomic mass too. |
Metalloids | -elements on both sides of the zigzag line (staircase) have properties of both metals & non-metals. |
Periods | - the periods on the PT are the ROWS numbered from 1-7 - atomic # increases from left to right - those in the same period have the same # of energy levels/shells - chemical properties are not ALL similar |
Groups | - families/groups on the PT are the columns numbered from 1-18 - same # of valence electrons. - chemical properties are very similar - group 1 is the most reactive & group 18 is the most inert (stable) |
Alkali Metals | - group 1 - highly reactive metals - so reactive that they can never be found uncombined in nature. - metals soft enough to be cut w/ a butter knife. |
Alkaline Earth Metals | - group 2 - fairly reactive metals - not as reactive as the alkaline metals but still never found uncombined in nature |
Transition Metals | - groups 3-12 - less reactive metals - hard dense metals that are useful as building materials, jewelry & coins. - also used as oxides to make paint & pigment |
Noble Gases | - group 18 - unreactive gases - do not react naturally / always found in their own nature - used in "neon" signs, balloons, & light bulbs |