CBSE Class 11-science Answered

Properties

Across the period

(left to right)

Down the group

(top to bottom)

Atomic size

Decreases

Increases

No. of valence electrons

Increases

Remains same

Metallic character

Decreases

Increases

Non-metallic character

Increases

Decreases

Electron affinity

Increases

Decreases

Electronegativity

Increases

Decreases

Ionisation energy

Increases

Decreases

Basic nature of oxides

Decreases

Increases

Melting point

Increases from Group I to Group IV and then decreases

Decreases in Groups I and II

Decreases in Groups III and IV

Increases in Groups V to VII

Boiling point

Increases from Group I to Group IV and then decreases

Decreases in Groups I and II

Decreases in Groups III and IV

Increases in Groups V to VII

Oxidising nature

Increases

Decreases

Reducing nature

Decreases

Increases