Metals, Non-metals and Metalloids

Properties of Metals They are usually shiny They are good conductors of electricity which is called conductivity They are solid at room temperature (except mercury which is liquid) Most are malleable (can be hammered into different shapes) Most are ductile (can be pulled into a long, thin wire) Most react with acids Examples: Gold (Au), Silver (Ag), Potassium (K), Tin (Sn), Lead (Pb)

Metal Mixtures Most metal object are mixtures of metallic elements from the periodic table Example: Stainless steel Is a mixture of mostly iron (Fe), nickel (Ni), and chromium (Cr) A metal produced by blending different metal elements together is called an alloy Example: Brass is an alloy of copper (Cu) and zinc (Zn)

Uses of metals Jewellery – such as gold and silver Art – artists use different metals to create glass different colours Aluminum foil Copper is used for electrical wiring

Properties of Non-Metals Many are gases at room temperature (a few are solid and one is a liquid) Solid non-metals do not have a shine – most are have a dull lustre Solid non-metals are brittle which means they break or shatter when bent or struck Are poor conductors of electricity Examples: Carbon (C), Sulfur (S), Oxygen (O), Chlorine (Cl), Iodine (I), Neon (Ne).

Non metal Elements in Air Composition of air is: 78% nitrogen 21% oxygen 0.9% argon And 0.1% neon, helium, krypton and compounds of water and carbon dioxide

Uses of non-metals Chlorine is used to disinfect water for drinking or swimming Bromine is used in dyes, medicines, pesticides and photography Helium balloons rise because helium is less dense than air Xenon used in bluish headlights of certain vehicles Neon and argon give off brightly coloured lights

Properties of Metalloids Have properties in between those of metals and non- metals All metalloids are solid at room temperature Some metalloids are weak conductors of electricity Examples: Boron (B), Silicon (Si), Germanium (Ge), arsenic (As)

Classwork AIM 10 AIM 11 Reminder: Computer Lab time to work on Element Project Friday March 8th Room 203