Group 7: Reactivity & Electronic Configurations Flashcards

All 4 cards in this deck

What is the order of reactivity of chlorine, bromine and iodine?

Chlorine > bromine > iodine — reactivity decreases down Group 7.

Give two reasons why an electron is gained less easily further down Group 7.

The outer shell is further from the nucleus and there is greater shielding (more shells), so there is less nuclear attraction for the extra electron.

How do displacement reactions show the order of reactivity of chlorine, bromine and iodine?

A more reactive halogen displaces a less reactive one from its halide solution (seen as a colour change). Chlorine displaces bromide and iodide; bromine displaces only iodide; so chlorine > bromine > iodine.

True or false? Astatine would displace iodine from sodium iodide solution.

False. Astatine is below iodine in Group 7, so it is less reactive and cannot displace iodine.