group 1(alkali metals), group 7(halogens) and group 0(noble gases) and transition elements

group one:

alkali metals have low density

reactivity increases as you go down group 1

when alkali metals react with non metals they form ionic bonds

compounds made in these reactions are white/solids/soluble

alkali metal+water=metal hydroxide+hydrogen

when a group 1 metal reacts with water the solution is alkaline

alkali metal+chlorine=metal chloride

potassium+oxygen=potassium superoxide and potassium peroxide

group 7:

two atoms are in the molecules of halogens in their elemental form

the most reactive halogens are found at the top of group 7

as you go down group 7 the increased atomic radius as you go down the group means there is less attraction between the outer electron shell and the nucleus. 

as the halogens react by gaining electrons in their highest electron shell this decreasing attraction means that elements lower in the group are less likely to gain an electron so reactivity decreases down the…