Question

explain the reason why basic nature of oxides decreases along a period and increases down the group ?

Answer 1

The acidic and basic nature depends on metallic property. Generally, metallic oxides are basic in nature and non metallic oxides are acidic,.
Now, along a group, the along a group the metallic character increases and so the oxides are always basic down the group.While, along the period the metallic character decreases and so the acidic nature of oxide increases along a period and hence basic nature decreases along the period.