Inorganic Chemistry - Group 7 (Halogens), Chlorine, Bromine, Iodine

Question 1

What is the colour and physical state of chlorine at room temperature?

Answer 1

A yellow - green gas

Question 2

What is the colour and physical state of bromine at room temperature?

Answer 2

A red - brown liquid

Question 3

What is the colour and physical state of iodine at room temperature?

Answer 3

A purple solid

Question 4

Use knowledge of trends in Group 7 to predict the properties of other halogens

Answer 4

Trend of gas to liquid to solid down the group because the melting and boiling points increase as you go down the group. From this, you can predict any halogens above chlorine will be a gases (their boiling points will be even lower) and any below iodine will be solids (their melting points will be even greater).

Question 5

Explain the trends in reactivities in Group 7 in terms of electrical configurations

Answer 5

The halogens react by gaining an extra electron in their outer shell, as you go down the group:

1. Outer shell becomes further from the nucleus
2. Electron shielding increases
3. Attraction decreases between nucleus and outer electrons.
4. Electrons are gained less easily
5. Halogens become less reactive