TOPIC: Metals vs Nonmetals Do Now: grab a lab up front and start filling in the symbols and atomic number for the elements Replace Calcium with Silicon and Manganese with Cadmium

Classifying the Elements 2/3 (67%) of elements are metals Remaining elements: non-metals & metalloids (semi-metals) Metalloids: some properties of metals & some properties of nonmetals Staircase: dividing line between metals & nonmetals elements to left are metals (except H) elements to right are non-metals

Properties of Metals Malleable – flattened into sheets Ductile – drawn into wires & tubes have Luster Good Conductors of heat & electricity Solid at room temperature (except Hg) Metals lose electrons & form positive ions “Metals are losers” Most reactive metal is Fr Most reactive family is Alkali Metals

So…metals don’t want electrons, they want to get rid of them

Properties of Nonmetals generally gases or solids (except Br2) solids are Brittle solids are Dull poor conductors of heat & electricity Nonmetals gain electrons & form negative ions “Nonmetals are winners” Most reactive nonmetal is F Properties: OPPOSITE of metals

So…nonmetals love electrons, they want to take electrons

Properties of Metalloids 4 on right of staircase: B,Si,As,Te, 2 on left of staircase: Ge,Sb Each metalloid has some metallic and some nonmetallic properties Example:Si shiny like metal but brittle like nonmetal

Most elements are solid at room temperature GASES Elements that are gases at STP Diatomics: H2, N2, O2, F2, Cl2 Monatomics: noble gases He, Ne, Ar, Kr, Xe, Rn Liquids (only 2 at room temp.) Br2 (non-metal) and Hg (metal)

Allotropes Different forms of element in same phase different structures and properties O2 and O3 - both gas phase O2 (oxygen) - necessary for life O3 (ozone) - toxic to life Graphite, diamond: both carbon in solid form