The substance that represents a compound among the given options is CO. The correct answer is (3) CO(g)
From the question,
We are to determine which of the given substances is a compound.
First, we will define a compound
A compound is a chemical species that is formed when two or more atoms join together chemically, with covalent or ionic bonds.
OR
A compound is a substance that contains atoms of two or more different elements, and these atoms are chemically joined together
NOTE: A molecule consisting of atoms of only one element is NOT a compound.
Among the given options, only CO satisfies the definition of a compound, because it contains two different elements, Carbon (C) and Oxygen (O).
Hence, the substance that represents a compound among the given options is CO. The correct answer is (3) CO(g)
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