Reactivity decreases down the group. Because of their high electronegativities they are oxidising agents and are able to gain electrons to form negative ions.Reactivity decreases for the same reason electronegativity decreases:•nuclear charge - the bigger the nuclear charge the higher the electronegativity• the distance between the nucleus and bonding pair of electrons. The shorter the distance the higher the electronegativity•the fewer the energy levels the smaller the shielding effect therefore the higher the electronegativity
Trend in Reactivity
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Specification: Edexcel Chemistry (8CH0), AS-level, Topic 4B: The elements of Group 7 (halogens). Topic: Group 7.
Key terms in this lesson
- oxidising agent
- A substance that accepts electrons from another species, causing it to be oxidised, while it is itself reduced.
- electronegativity
- The ability of a bonded atom to attract the shared pair of electrons in a covalent bond towards itself.
More in Group 7
- Group 7 Elements
- Trends in Melting and Boiling Temperature
- Trend in Electronegativity
- Reactions with Group 1 and 2 Metals
- Halogen-Halide Displacement Reactions
- Halogen Disproportionation Reactions
- Reaction of Halides with Sulfuric Acid
- Sodium Chloride
All 14 lessons in Group 7 · All Edexcel AS-level Chemistry topics