TOPIC Metals vs Nonmetals Do Now grab a
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 Br 2) 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 6 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: H 2, N 2, O 2, F 2, Cl 2 – Monatomics: noble gases He, Ne, Ar, Kr, Xe, Rn • Liquids (only 2 at room temp. ) – Br 2 (non-metal) and Hg (metal)
Allotropes • Different forms of element in same phase – different structures and properties • O 2 and O 3 - both gas phase – O 2 (oxygen) - necessary for life – O 3 (ozone) - toxic to life • Graphite, diamond: – both carbon in solid form
- Slides: 10