The correct order of dipole moment is : — Chemical Bonding Chemistry Question

💡 Solution & Explanation

Step 1: Identify that methane (CH_4) is a highly symmetric regular tetrahedral molecule with a net dipole moment of zero. Step 2: Among the remaining polar molecules: NF_3 has a small dipole moment (~0.24 D) because the N-F dipoles oppose the lone pair dipole. NH_3 has a larger dipole moment (~1.47 D) because the N-H dipoles reinforce the lone pair dipole. H_2O has the largest dipole moment (~1.85 D) due to its highly polar O-H bonds and two reinforcing lone pairs in a bent geometry. Step 3: Thus, the correct increasing order of dipole moment is CH_4 < NF_3 < NH_3 < H_2O. Therefore, the correct option is (a).