The atoms get bigger going down the group. The atomic radius increases because down the group and extra main level is added.The metallic bonds are stronger than the metallic bonds of group 1 metals as they involve doubly charged ions and 2 delocalised electrons per atom. Going down the group, the sea of delocalised electrons is further away from the nucleus so the strength of the metallic bonds decreases down the group and the melting point decreases down the group.
Physical Properties
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Specification: AQA Chemistry (7404), AS-level, 3.2.2 Group 2, the alkaline earth metals. Topic: Group 2.
Key terms in this lesson
- Delocalised electrons
- Electrons that are not associated with a single atom or bond and are free to move throughout a structure.
- Atomic radius
- A measure of the size of an atom, found by measuring the distance between two adjacent nuclei and dividing by two.
- Group
- A vertical column of the periodic table, containing elements with the same number of outer-shell electrons.
More in Group 2
- Group 2 Elements
- Ionisation Energies
- Calcium
- Reaction with Water
- Solubility of Hydroxides
- Solubility of Sulfates
All 7 lessons in Group 2 · All AQA AS-level Chemistry topics