group 7

Question 1

halogens?

Answer 1

diatomic molecules e.g F2 , Cl2

Question 2

reactivity?

Answer 2

reactivity decreases down the group because atomic radius causes the nucleus to be weakened by shielding
the melting and boiling points increase the group because they are more electrons and more london forces so more energy is required to break the intermolecular forces

Question 3

chlorine

Answer 3

pale green/colourless
but with organic solvent e.g cyclohexane
chlorine its colourless

Question 4

bromine

Answer 4

bromine its yellow
but with organic solvents : cyclohexane
yellow

Question 5

iodine

Answer 5

iodine it’s brown solution
but with organic solvents
its purple

Question 6

disproportionation

Answer 6

reaction where a element stimulatingly oxides and reduces

Question 7

chlorine?

Answer 7

its toxic but kills bacteria but the benefits outweigh the toxic effects and is used to treat water
its also used as a bleach to kill bacteria Cl with cold dilute NaOH solution( colour of the halogen will fade to colourless)