Medium Practice — Set 1

Quick Recap — Hybridisation & Geometry Calculations

• Steric number (bond pairs + lone pairs) sets hybridisation: 2 $\to sp$, 3 $\to sp^2$, 4 $\to sp^3$, 5 $\to sp^3d$, 6 $\to sp^3d^2$.
• Lone pairs on the central atom: $NH_3$ (1), $H_2O$ (2), $ClF_3$ (2), $XeF_2$ (3), $XeF_4$ (2).
• MOT: bond order $=\dfrac{N_b-N_a}{2}$; unpaired electrons set magnetism.
• Dipole moment cancels in symmetric molecules; adds in bent/pyramidal ones.