Methane (CH4) is a non-polar molecule, and it does not have a specific electronegativity value. Electronegativity is a property of individual atoms, not molecules. In methane, carbon (C) has an electronegativity of 2.55, and hydrogen (H) has an electronegativity of 2.20. The difference in electronegativity between carbon and hydrogen is 0.35, which is relatively small. This small difference means that the C-H bonds in methane are considered non-polar covalent bonds.
Since methane is a symmetrical molecule with these non-polar bonds, the overall molecule is non-polar. This lack of polarity is why methane does not have a specific electronegativity value as a molecule.