What is the molecular geometry and molecular polarity of XeCl4`
The Correct Answer and Explanation is:
Correct Answer:
- Molecular Geometry: Square planar
- Molecular Polarity: Nonpolar
Explanation
Xenon tetrachloride (XeCl₄) is a compound where the central atom is xenon (Xe), a noble gas, and it is bonded to four chlorine (Cl) atoms. To determine the molecular geometry and polarity of XeCl₄, we use Valence Shell Electron Pair Repulsion (VSEPR) theory, which helps predict the three-dimensional shape of molecules based on electron pair repulsion around the central atom.
Xenon has 8 valence electrons. Each of the four Cl atoms forms a single bond with Xe, using 4 electrons. This leaves 4 electrons (or 2 lone pairs) on the xenon atom. Therefore, the total number of electron domains around Xe is 6 (4 bonding pairs + 2 lone pairs).
According to VSEPR theory, six electron domains arrange themselves in an octahedral electron geometry to minimize repulsion. When two of these are lone pairs, they position themselves opposite each other to be as far apart as possible. The remaining four positions are occupied by bonding pairs, resulting in a square planar molecular geometry.
In a square planar shape, the four chlorine atoms occupy the corners of a square on the same plane, and the lone pairs are above and below this plane. Since all Cl atoms are positioned symmetrically and have the same electronegativity, the individual dipole moments cancel out.
Thus, even though the Xe–Cl bonds are polar (due to the difference in electronegativity between Xe and Cl), the symmetry of the square planar shape causes these dipoles to cancel, making the overall molecule nonpolar.
In summary, XeCl₄ has a square planar molecular geometry and is nonpolar because of its symmetric shape, which allows the bond dipoles to cancel out evenly.
