Which substance is a molecule?
1. ch4
2. naf
3.ar
4. pb

Molecules are substances that contain two or more elements, if these elements are different, then the substance is also a compound.
However, considering only the definition of a molecule, it is evident that both CH4 and NaF are molecules as they contain more than one element.

In fact, all of these (Ch4, NaF, Ar, and Pb) are molecules.

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