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Question
State the property trends in general of elements on moving down in a group of the periodic table.
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Solution
Trends in a group:
- Number of shells and valence electrons: As we move down in a group the number of shells increase and valence electrons in a group remains the same.
- Valency: Valency of all elements is the same.
- Properties of elements:
(a) Metallic character increases,
(b) Non-metallic character decreases - Atomic size increases.
`"F>Cl>Br>I"/"Reactivity decreases"`
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