molecule or polyatomic ion polar or atom closest to nonpolar? negative side polar nonpolar polar nonpolar polar nonpolar H2S CH;F Cl2
The Correct Answer and Explanation is:
Here is the completed chart with correct answers and an explanation:
| Molecule or Polyatomic Ion | Polar or Nonpolar? | Atom Closest to Negative Side |
|---|---|---|
| H₂S | ✅ Polar | ✅ S (Sulfur) |
| CH₃F | ✅ Polar | ✅ F (Fluorine) |
| Cl₂ | ✅ Nonpolar | (No atom closer; same atom) |
Explanation
The polarity of a molecule is determined by the difference in electronegativity between atoms and the geometry of the molecule. A polar molecule has a partial positive side and a partial negative side, resulting in a dipole moment, while a nonpolar molecule has a balanced charge distribution.
- H₂S (Hydrogen Sulfide)
H₂S is polar. Though sulfur is less electronegative than oxygen (as in H₂O), it is still significantly more electronegative than hydrogen. The bent molecular shape (due to lone pairs on sulfur) means the dipole moments of the H–S bonds do not cancel out. The electron density is higher around sulfur, making it the negative side of the molecule. - CH₃F (Fluoromethane)
CH₃F is also polar. Fluorine is the most electronegative element, pulling electrons strongly toward itself in the C–F bond. The rest of the molecule (the CH₃ group) is less electronegative and cannot counterbalance the pull from fluorine. The molecular geometry does not cancel out the dipole, making fluorine the atom closest to the negative side. - Cl₂ (Chlorine molecule)
Cl₂ is a nonpolar molecule. It consists of two identical chlorine atoms sharing electrons equally. Since there is no difference in electronegativity and the molecule is linear and symmetric, there is no dipole moment. Therefore, no single atom is closer to the negative side—the electron distribution is symmetrical.
Understanding polarity is crucial because it affects molecular interactions, such as solubility, boiling/melting points, and intermolecular forces like hydrogen bonding and dipole-dipole attractions.
