Indian Forest Service (Mains), Chemistry optional · 2025 · Paper I
Q2(c)(i). Ordering molecular dipoles
Question
Arrange NH₃, NF₃ and H₂O in increasing dipole moment, giving reasons.
Answer in brief
The order is NF₃ < NH₃ < H₂O, approximately 0.24 < 1.47 < 1.85 D.
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Coversdipole momentNH₃ vs NF₃ dipolelone pair momentvector addition of bond dipoles
All parts of Question 2
- 2(a)(i) Hydrogen equation in spherical coordinates10 marks
- 2(a)(ii) Box length from an emission frequency5 marks
- 2(b)(i) Lifetime and spectral uncertainty5 marks
- 2(b)(ii) Dissociation energies of dioxygen species10 marks
- 2(c)(i) Ordering molecular dipoles5 marks
- 2(c)(ii) Bonding and magnetism of B₂5 marks