Respuesta :
They are all diatomic
Reactivity decreases as you go down
All halogens need to gain 1 electron
Reactivity decreases as you go down
All halogens need to gain 1 electron
They get darker in colour as you go down the list, have a higher covalent radius as you go down the list, have a lower electronegativity as you go down the list, etc.
Hope it helped!
Hope it helped!