The molecular structure of xenon dichloride (XeCl2) can be predicted using VSEPR (Valence Shell Electron Pair Repulsion) theory. In this compound, the xenon atom is the central atom, and it is surrounded by two chlorine atoms.
Xenon has a total of 8 valence electrons, and each chlorine atom contributes 7 electrons, giving a total of 14 valence electrons for the two chlorines. When we consider the bonding, xenon uses 2 of its electrons to form single bonds with each chlorine atom, resulting in 6 remaining electrons. These leftover electrons will be arranged as three lone pairs on the xenon atom.
According to VSEPR theory, the arrangement of electron pairs around the xenon atom will determine the molecular geometry. With 2 bonding pairs (from Xe-Cl bonds) and 3 lone pairs, the electron geometry is trigonal bipyramidal. However, because there are lone pairs, the molecular shape changes to linear.
In terms of bond angles, the ideal angle for a trigonal bipyramidal arrangement is 120° and 90°. However, because the lone pairs occupy equatorial positions and push against the bonding pairs, the Xe-Cl bond angle adjusts to 180° in the linear configuration.
In summary, XeCl2 has a linear molecular structure with bond angles of 180° due to the presence of three lone pairs of electrons on the central xenon atom.