Group 7

what group are group 7

halogens

how does mp/bp change down a group

increases jut still relatively low

why does bp/mp increase down the group

more electrons = more LDF

colour and state of fluorine at room temp

yellow- gas

colour and state of chlorine at room temp

dense yellowy green - gas

colour and state of bromine at room temp

red brown- liquid

colour and state of iodine at room temp

dark grey- solid

what does iodine do that others dont

sublimes- goes from solid to gas without liquid- releases purple fumes

are halogen soluble in water

yes

colour of chlorine dissolved in water

pale green

colour of bromine dissolved in water

orange

colour of iodine dissolved in water

brown

polarity of halogens

no polar

what does their polarity mean for their ability to dissolve in wtaer

don’t dissolve well

what do they prefer to dissolve in

organic solvent if cyclohexane

colour of chlorine dissolved in cyclohexane

pale green

colour of bromine when dissolved in cyclohexane

orange

colour of iodine when dissolved in cyclohexane

violet

what block are they in

p block

what ions do they form

1-

are halogen oxidising or reducing agents

oxidising agents- they are reduced

how many electrons in outer p sub shell

5

difference in electrons compared to next noble gas

each element has one fewer electron than the next noble gas

electron configuration of F

[He] 2s2 2p5

electron configuration of Cl

[Ne] 3s2 3p5

electron configuration of Br

[Ar] 4s2 4p5

electron configuration of I

[Kr] 5s2 5p5

electron configuration of At

[Xe] 6s2 6p5

What are the most reactive non metals

Halogens

Are halogens strong oxidising agents

Yes

What happens to oxidising power as you move down the group

Decreases

What happens to reactivity down the group and why

Decreases- atomic radius increases,electron shielding increases, attraction from nucleus to incoming e- decreases

Half equation of chlorine

Cl2 (g) + 2e- → 2Cl- (g)

What happens in displacement reaction between halogens and halides

Halogen acts as an oxidising again and oxides halide ion into a halogen, halogen gains electrons, halogen is reduced to form the halide ion

Full equation of chlorine + potassium bromide (halide salt)

Cl2 + 2KBr → 2KCl + Br2