Intro To Halogens

Question 1

Which halogens are our main focus

Answer 1

fluorine, chlorine, bromine and iodine.

Question 2

Main oxidation state for these elements in halogens

Answer 2

-1

Question 3

What are halogens

Answer 3

Group 7

Question 4

Fluorine, chlorine, bromine & iodine are what ions

Answer 4

Halide ions
(Halogens with negative charge)

Question 5

Structure of halide ions

Answer 5

They form diatomic molecules e.g. F2 and only have weak London forces between them.

Question 6

Appearance, colour and state of fluorine

Answer 6

Pale yellow gas at RT
nothing when in non-polar solvents
nothing when reacts with water
Melting and boiling point low

Question 7

Appearance, colour and state of chlorine

Answer 7

Pale green gas at RT
Pale green sol. in non-polar solvents
Pale green sol. in water
Melting and boiling low

Question 8

Appearance, colour and state of Bromine

Answer 8

Dark red liquid at RT
Orange sol. in non-polar solvents
Orange sol. in water
MP low
BP high

Question 9

Appearance, colour and state of Iodine

Answer 9

Grey solid at RT
Purple sol. in non-polar solvents
Brown sol. in water if excess iodine (I-) present
Melting and boiling point high

Question 10

Melting point trend for halide ions

Answer 10

Increase surface area and molecule has more electrons
Stronger london forces occur in the molecule
More energy required to overcome these forces
MP increases as you go down

Question 11

Trend in Electronegativity in halide ions

Answer 11

Nuclear charge increases
Shielding increases
Core charge stays the same
Atomic radius increases
Nuclear attraction decreases
Electronegativity decreases as you go down