Group 7, the halogens

Question 1

what colour gas is F2

Answer 1

pale yellow gas

Question 2

Cl gas colour

Answer 2

pale green

Question 3

Br liquid colour

Answer 3

Brown-orange liquid

Question 4

Iodine solid colour?

Answer 4

black solid precipitate

Question 5

does BP increase/ decrease down Group 7

Answer 5

Increases:
- size of the atoms get bigger down the group so there are more stronger van der Waals forces of attraction, so requires more energy to break

physical state changes from Gas->solid down the group

Question 6

Does electronegativity increase or decrease down group 7

Answer 6

Decrease:
- Atoms get larger down the group, so distance between outer electron and nucleus increases, so weaker electrostatic forces of attraction between them

• also there is increased shielding

Question 7

more reactive halogens will DISPLACE less reactive…

Answer 7

Halide ions

Question 8

does reactivity increase or decrease down group 7

Answer 8

for reactions to occur an atom needs to be able to gain an electron ( 1- ions)

It is harder to do this as we go down the group due to an increase in the size of atoms, therefore reactivity decreases

Question 9

are Halogens less oxidising or more oxidising down the group

Answer 9

LESS oxidising down the group

-show this by reacting halogens with halide ions

Question 10

A HALOGEN WILL DISPLACE A HALIDE ION IF THE HALIDE ION IS…

Answer 10

LOWER in the periodic table

• LESS reactive so displaced