What is a pure substance that contains two or more elements?

1 Answer
Jan 9, 2017

Answer:

A pure substance that contains two or more elements is a compound.

Explanation:

Compounds can be ionic or covalent . Many ionic compounds are composed of a metal and a nonmetal, such as sodium chloride, #"NaCl"#, common table salt. Ionic compounds can also contain polyatomic ions, such as the nitrate ion, #"NO"_3^(-)"#. An example would be potassium nitrate, #"KNO"_3"#.

Covalent compounds are formed when atoms share their valence electrons. Such compounds contain one or more covalent bonds. They include water, #"H"_2"O"# and carbon dioxide, #"CO"_2"#.