Groups on the periodic table
Group 1: Alkali Metals
°Li, Na, K, Rb, Cs, Fr
°they have low densities
°Soft
°Are good conductors of heat & electricity
°Form cations with +1 charge
°React vigourously with water
Group 2: Alkali Earth Metals
° Be, Mg, Ca, St, Ba
° Silvery
° Form cations with +2 charge
° Reactivity witb water increases down the group
° Good conductors of heat & electricity
° Burn in air to form solid oxides
Group 17: Halogens
° Diatomic eg. Cl², F², Be², I²
° F² & Cl² are yellow to green gases
° Br² is a reddish brown liquid
° I² form purple crystals
° All halogens arw non-metals
° Form anions with the charge -1
° They havd low melting points and boiling points.
Group 18: Noble Gases
° He, Ne, Ar, Kr, Xe, Rn
° They re extremely unreactive. A few krypton and xenon compounds are known, therefore reactivity increase down the group
° Boiling poibts increase down the group