Group 7 Flashcards
What is electronegativity?
It is the power of an atom in a molecule to attract electrons in a covalent bond to itself
Explain the trend in electron negativity down period seven
It decreases
Explain the trend and atomic radius down period seven
it increases due to the increasing number of shells and the nucleus is less able to attract bonding pair of electrons
Explain the trend in melting and boiling points down period seven.
It increases down the group as molecules become larger as they have more electrons or stronger and larger VDW forces as an intermolecular forces get larger more energy is required to break the forces which increases melting and boiling points
Fluorine is
A yellow pel gas
Chlorine is
A greenish reactive gas
Bromine is
Red brownish liquid
Iodine is
Black solid
Reactivity generally ……. Down the group.
Decreases
Explain displacement
A halogen reacting with a metal halide in the solution the halide will displace the reactive halogen for example, chlorine will displace bromine
What are the two tests for halide ions?
Reactions with sulphuric acid
Reaction with silver nitrate
What happens when chlorine reacts with sulphuric nitrate
It produces hydrogen sulphate
It is an acid base reaction
White misty fumes
What happens when chlorine reacts with sulphuric nitrate
It produces hydrogen sulphate
It is an acid base reaction
White misty fumes
What is the equation for when chlorine reacts with sulphuric acid? 
NACL + H2S04 ——> NAHS04+ HCL
What happens when bromine reacts with sulphuric acid?
It produces hydrogen sulphate and SO2
Why steamy fumes are formed and there is a brown vapour from the bromine