Final answer:
Chlorine gas (Cl2) has a nonpolar molecule due to the symmetric sharing of electrons between the two chlorine atoms with the same electronegativity, resulting in no net dipole moment.
Step-by-step explanation:
Chlorine gas (Cl2) is composed of two chlorine atoms sharing a single covalent bond. Since both atoms have the same electronegativity, the electron density around the Cl2 molecule is symmetrical, making it a nonpolar molecule. The electronegativity difference (AEN) for a Cl-Cl bond is 3.0-3.0=0 which falls well below the threshold that typically defines polar covalent bonds (AEN > 0.5). Therefore, the Cl2 molecule does not have a net dipole moment, which is characteristic of nonpolar molecules.
Chlorine gas (Cl2) is nonpolar because the electronegativity difference between the two chlorine atoms is zero. The two chlorine atoms share the pair of electrons in the single covalent bond equally, resulting in symmetrical electron density surrounding the Cl2 molecule. This is also confirmed by the fact that the electronegativity difference is very small (<0.4), which classifies it as a nonpolar covalent bond.