The number of non-polar molecules from the following is . HF, H2O, SO2, H2, CO2, CH4, NH3, HCl, CHCl3, BF3
Answer
4
Solution
Non-polar ⇒ identical atoms, or polar bonds arranged symmetrically so that bond dipoles cancel ( = 0)
H2: identical atoms ✓
CO2 (linear), BF3 (trigonal planar), CH4 (tetrahedral): dipoles cancel ✓
HF, HCl (polar bond); H2O, SO2 (bent); NH3 (pyramidal); CHCl3 (unsymmetrical) ⇒ polar ✗
∴ Non-polar molecules = 4
Answer: 4