The Electronegativity difference between carbon and oxygen is 1. Carbon and Oxygen both are elements. Where Carbon is present in a solid form, oxygen presents itself in the form of a gas having two molecules of oxygen covalently bonded with each other.
A covalent bond between carbon and oxygen results in a gaseous compound called carbon dioxide, comprising of a single carbon molecule and two molecules of oxygen. In chemistry, elements are the most basic classes of substances that can be formed, and all compounds are produced by varying combinations of these very basic elements. They are all listed in a table called the periodic table.