Halogens

Question 1

Fluorine
Colour
Physical state at rt

Answer 1

Pale yellow

gas

Question 2

Chlorine
Colour
Physical state at rt

Answer 2

Green

Gas

Question 3

Bromine
Colour
Physical state at rt

Answer 3

Red-brown

Liquid

Question 4

Iodine
Colour
Physical state at rt

Answer 4

Grey

Solid

Question 5

Halogens get….. reactive going down

Answer 5

Less

Question 6

Halogens displace

Answer 6

Less reactive halide ions from solution

Question 7

When displacement reactions occur there is……

this can be made more obvious by

Answer 7

Colour changes

Shaking in organic solvent like hexane
Halide will dissolve in hexane. Settles as top layer

Question 8

Cl2 + kcl

Start end

Answer 8

Start- both colourless

Aqueous- no reaction (colourless)

Organic solution- no reaction( colourless )

Question 9

Kcl + br2

Answer 9

Start- yellow

Aqueous-no reaction ( yellow)

Organic solution -no reaction ( orange)

Question 10

Kcl+ i2

Answer 10

Start-orange/brown

Aqueous-no reaction( orange/brown)

Organic-no reaction ( purple)

Question 11

Kbr+ cl2

Answer 11

Start -colourless

Aqueous-Br2 (yellow)

Organic-br2( orange)

Question 12

Kbr+br2

Answer 12

Start- yellow

Aqueous-no reaction ( yellow)

Organic - no reaction ( orange)

Question 13

Kbr+i2

Answer 13

Start- orange/brown

Aqueous-no reaction( orange /brown)

Organic -no reaction ( purple)

Question 14

Ki +cl2

Answer 14

Start-colourless

Aqueous-i2 (orange/brown)

Organic -i2(purple)

Question 15

Ki+ br2

Answer 15

Start- yellow

Aqueous- i2 (orange/brown )

Organic -i2( purple)

Question 16

Ki+i2

Answer 16

Start - orange/ brown

Aqueous-no reaction ( orange/ brown)

Organic- no reaction ( purple)

Question 17

3 stages for testing for halides

+ general equation

Answer 17

Add dilute nitric acid to remove and interfering ions

Add silver nitrate

Ag+. + x- = agx

Test with ammonia solution

Question 18

Results of testing for halides ( 2 parts)

Answer 18

Chloride-white precipitate- dissolves in dilute ammonia

Bromide-cream precipitate - dissolves in conc ammonia

Iodide- yellow precipitate- insoluble in conc ammonia

Question 19

Disproportionation

Answer 19

Simultaneously oxidised and reduced