Question

What is the nature of oxide formed

Answer 1

Basic if metallic.
Acidic if non metallic.

Answer 2

Metal oxides. Metal oxides are crystalline solids that contain a metal cation and an oxide anion. They typically react with water to form bases or with acids to form salts. MO + H2O → M(OH)2 (where M = group 2 metal) Thus, these compounds are often called basic oxides.