Properties of Group 7
I can describe patterns in the properties of group 7 elements and explain how these are determined by their electron structures.
Properties of Group 7
I can describe patterns in the properties of group 7 elements and explain how these are determined by their electron structures.
Lesson details
Key learning points
- Group 7 elements are very reactive and their reactivity decreases down the group.
- Moving down Group 7 elements, atomic mass, density, and melting and boiling points increase.
- In chemical reactions, atoms of Group 7 elements gain one outer electron making just full electron shells.
- Going down Group 7, the force attracting an extra electron reduces with the distance of each shell from the nucleus.
- Halogens are elements, halides are salts.
Common misconception
Pupils often forget that the halogens are diatomic molecules.
Explanation of the bonding to form molecules helps to explain why they exist as diatomic molecules.
Keywords
Salts - are ionic compounds formed from positive and negative ions electrostatically attracted to each other.
Halogens - are reactive non-metallic elements in Group 7 of the periodic table which react with metals to form salts.
Halides - are the name of salts formed from halogens, e.g sodium chloride (NaCl).
Diatomic - element consists of two atoms of the same type, chemically bonded together.
Equipment
None required.
Licence
This content is © Oak National Academy Limited (2024), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).
Video
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Starter quiz
6 Questions
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