Which of the following molecules are polar

Which of the following molecules are polar? Mark all that apply (it might be one or more correct answers). XeO
SiCl
Br
C
Br
SeCl
XeO
SeCl
C
Br
SiCl
Br

The Correct Answer and Explanation is:

Let’s analyze the polarity of the given molecules one by one:

1. XeO₂ (Xenon dioxide):
   Xenon is a noble gas and tends to form covalent bonds with oxygen. The molecule is bent due to the lone pairs on xenon, which creates an asymmetry in the electron distribution. This asymmetry leads to a polar molecule. Hence, XeO₂ is polar.
2. SiCl₂ (Silicon dichloride):
   Silicon dichloride has a tetrahedral geometry, with chlorine atoms symmetrically distributed around the silicon atom. Because the electronegativity difference between Si and Cl is not very large, but the molecule is symmetrical, the dipoles cancel each other out, making the molecule nonpolar. Hence, SiCl₂ is nonpolar.
3. Br₂ (Bromine):
   Bromine is a diatomic molecule with identical atoms. Since both atoms have the same electronegativity, the electron distribution is symmetric. Therefore, Br₂ is nonpolar.
4. C₂Br₂ (Dibromocarbon):
   The molecule is linear, with the two bromine atoms on opposite sides of the carbon atoms. Because of the symmetry, the dipoles cancel out, making the molecule nonpolar.
5. SeCl₆ (Selenium hexachloride):
   This molecule has an octahedral geometry, and since selenium is more electronegative than chlorine, there will be a net dipole moment. However, because of its symmetrical geometry, the molecule has no overall dipole moment. So, SeCl₆ is nonpolar.

In summary:

• XeO₂: Polar
• SiCl₂: Nonpolar
• Br₂: Nonpolar
• C₂Br₂: Nonpolar
• SeCl₆: Nonpolar