Which compound would decompose faster when heated mgco3 or caco3?

Caco3 would decompose faster as it is less stable as compared to mgco3 due to a lower electronegativity difference between calcium and carbonate ions.

Non metal is an element or substance that is not a metal metal is a solid material that is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivitymetalloid is an element (e.g., germanium or silicon) whose properties are intermediate between those of metals and solid nonmetals. they are electrical semiconductors.