A. Is XeF
polar or nonpolar? B. Is SO
Cl
polar or nonpolar? C. Is NO
Cl polar or nonpolar?
The Correct Answer and Explanation is:
A. Is XeF₂ polar or nonpolar?
Correct Answer: Nonpolar
B. Is SOCl₂ polar or nonpolar?
Correct Answer: Polar
C. Is NOCl polar or nonpolar?
Correct Answer: Polar
Textbook-Style Explanation
The polarity of a molecule depends on both the polarity of its individual bonds and the shape of the molecule, which determines whether the dipole moments cancel out.
A. Xenon Difluoride (XeF₂)
XeF₂ has a linear molecular geometry, resulting from the AX₂E₃ electron domain configuration. Xenon has 5 electron groups (2 bonding pairs and 3 lone pairs), and the three lone pairs occupy equatorial positions to minimize repulsion. The two fluorine atoms are positioned 180° apart. Although each Xe–F bond is polar due to the high electronegativity of fluorine, the linear shape causes the bond dipoles to cancel out symmetrically.
Therefore, XeF₂ is a nonpolar molecule despite having polar bonds.
B. Thionyl Chloride (SOCl₂)
SOCl₂ has a trigonal pyramidal geometry. Sulfur is the central atom, bonded to one oxygen atom (via a double bond) and two chlorine atoms. It also has one lone pair. This gives it an AX₃E shape, which is asymmetrical. The electronegativity differences between S–O and S–Cl bonds, combined with the asymmetry due to the lone pair, create a net dipole moment.
Thus, SOCl₂ is polar.
C. Nitrosyl Chloride (NOCl)
NOCl has a bent molecular shape around the nitrogen atom. It consists of nitrogen single bonded to chlorine and double bonded to oxygen. Due to the differing electronegativities of oxygen and chlorine and the bent shape, the dipoles do not cancel.
As a result, the molecule has a net dipole moment.
Therefore, NOCl is polar.
Summary
- XeF₂ → Nonpolar (linear shape, dipoles cancel)
- SOCl₂ → Polar (trigonal pyramidal, asymmetrical)
- NOCl → Polar (bent shape, uneven electronegativity distribution)
