Group 7 and Group 0

G7 also known as

Halogens

G0 also known as

Noble Gases

the 4 G7 that you need to know

fluorine

chlorine

bromine

iodine

fluorine

poisonous yellow gas, very reactive

chlorine

poisonous green gas, less reactive

bromine

red/brown volatile liquid, poisonous

Iodine

dark grey solid, can form poisonous vapours, is also an antiseptic

in what form do G7 elements exist and what kind of bonds

diatomic molecules, by forming covalent bonds

melting and boiling point in G7

increases as you go down the group

reactivity in G7

decreases as you go down the group

why does reactivity decrease as you go down G7

the atoms radius increases as you go down the group

therefore the electrons in the outermost shell get further away from the positive nucleus 

the attractive force needed to pull an electron towards the atoms gets weaker (as it forms negative ions)

if it cant attract an electron it cant react

G7 when they form ions

halogen —→ halide

fluorine —→ fluoride

chlorine —→ chloride

etc

properties of G0/noble gases

colourless gases

inert

boiling point increases as you go down the group

non flammable

why are noble gases/G0 inert

because they all have full outer shells so they don’t need to react

in what form do G0 atoms exist and why

as singular atoms

because they are inert