: 200
Xenon forms compounds due to its relatively low ionisation energy (large atom, electrons far from nucleus) and the high electronegativity of fluorine and oxygen. Key compounds: XeF2 (SN=5, sp3d, linear, 3 lone pairs equatorial). XeF4 (SN=6, sp3d2, square planar, 2 lone pairs trans). XeF6 (SN=7, sp3d3, distorted octahedral, 1 lone pair). XeO3 (SN=4, sp3, trigonal pyramidal, 1 lone pair). XeO4 (SN=4, sp3, tetrahedral, 0 lone pairs). XeOF2 (SN=5, sp3d, T-shaped, 2 lone pairs). XeOF4 (SN=6, sp3d2, square pyramidal, 1 lone pair). XeO2F2 (SN=5, sp3d, see-saw, 1 lone pair). Preparation: Xe + F2 at different ratios/conditions gives XeF2, XeF4, XeF6. XeO3 is formed by hydrolysis of XeF6. XeF2 is a mild fluorinating agent. XeO3 is dangerously explosive. All xenon-fluorine bonds are relatively weak. Xenon compounds are important for JEE because they systematically test VSEPR, hybridisation, and the concept of expanded octets.