topic: metals vs nonmetals do now: take 3 different colors of crayons
TRANSCRIPT
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 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
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
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