NEET2006ChemistryChemical Bonding and Molecular StructureActual
The electronegativity difference between N and F is greater that that between N and H yet the dipole moment of NH ₃ (1.5 D) is larger than that of NF ₃(0.2 D ) . This is because:
Options
- AIn ( NH ₃ ) as well as in ( NF ₃ ) the atomic dipole and bond dipole are in the same direction
- BIn ( NH ₃ ) the atomic dipole and bond dipole are in the same direction whereas in ( NF ₃ ) these are in oppos
- CIn ( NH ₃ ) as well as ( NF ₃ ) the atomic dipole and bond dipole are in opposite directions
- DIn ( NH ₃ ) the atomic dipole and bond dipole are in the opposite directions whereas in ( NF ₃ ) these are in
Correct answer
C. In ( NH ₃ ) as well as ( NF ₃ ) the atomic dipole and bond dipole are in opposite directions
Step-by-step solution
The electronegativity of N is greater than that of H _ in NH ₃ , but in NF ₃ , the electronegativity of F is greater than that of N . In NH ₃ , the atomic dipole and bond dipole are in the same direction, whereas in NF ₃ , these are in opposite directions. Related Theory The ammonia molecule has a permanent electric dipole moment equal to 1. 47 D . A Caution The larger the difference in electronegativity, the larger the dipole moment.