Paper: CSIR-NET December 2017 · Subject: Inorganic Chemistry · Chapter: Chemical Bonding · Topic: Chemical Bonding – General · Marks: 2 · Difficulty: Easy
Geometries of $\mathrm{SNF}_{3}$ and $\mathrm{XeF}_{2} \mathrm{O}_{2}$ respectively, are
(a)square planar and square planar
(c)square planar and trigonal bipyramidal
(d)tetrahedral and trigonal bipyramidal
(b)tetrahedral and tetrahedral
Answer
Answer: D ✓ checked by 4AB · confidence high
Book printed (d).
Explanation
SNF₃ (thiazyl trifluoride, NSF₃): S(VI) forms one S≡N and three S–F bonds and has no lone pair → 4 electron domains → tetrahedral. XeO₂F₂: Xe(VI) has 8 valence electrons; two Xe=O and two Xe–F bonds use 6, leaving one lone pair → 5 electron domains → trigonal bipyramidal (see-saw molecular shape). Hence tetrahedral and trigonal bipyramidal — option (d). (The source prints the option labels in the order a, c, d, b.)