Question

calcium and selenium which will form more acidic oxide why​

Answer 1

Calcium ( Ca) is a metal. It forms an oxide CaO ( Calcium Oxide) that is also called quick lime. This oxide is basic in nature as its a metal oxide.

Metal Oxides are basic in nature.

Selenium is a non metal. It forms Selenium dioxide . This is an acidic oxide because it's a non metal oxide .

Non Metal Oxides are acidic in nature.

•°• Out of Calcium and Selenium , Selenium forms an acidic oxide because it's non metal oxide.