which best describes a compound such as magnesium oxide?\n an impure substance that is made up of two…

which best describes a compound such as magnesium oxide?\n an impure substance that is made up of two elements\n a mixture of two uncommon substances\n a mixture of two common elements\n a pure substance that is made up of different elements
Answer
Brief Explanations:
A compound is a pure substance formed by chemical combination of different elements. Magnesium oxide ($MgO$) is made of magnesium ($Mg$) and oxygen ($O$) elements chemically bonded together. It is not a mixture or an impure substance.
Answer:
a pure substance that is made up of different elements