Paper 2 - The Halogens

Question 1

Explain the trend in reactivity in Group 7 in terms of electronic
configurations

Answer 1

• Halogen atoms have 7 electrons in their outer shell. They can gain one electron to form a -1 ion
• The easier it is for a halogen to attract an electron, the more reactive the halogen will be.
• The further down group 7, the less reactive the halogens are as it gets harder to attract the extra electron to fill the outer shell since its atomic radius is larger