Which best describes a compound such as magnesium oxide? an impure substance that is made up of two elements a mixture of two uncommon substances a mixture of two common elements a pure substance that is made up of different elements

A   compound such as magnesium oxide is best described as a pure substance that is made up of different elements. Magnesium oxide for instance, is made up of magnesium and oxygen which are two different elements. Magnesium oxide is a pure compound and not a mixture because its constituent elements can not be separated by physical methods.

It can be classified based on its

Answer//the law of conservation of mass.;