Which of the following sets of molecules/ions has exactly ONE lone pair of electrons on the central atom of every species in that set?

Step-by-step solution

Let us calculate the number of lone pairs on the central atom for each species. Number of lone pairs = Valence electrons - Electrons shared in bonds 2 Option 1: H ₂ O : Central atom O has 6 valence electrons. Shared = 2. Lone pairs = 6 - 2 2 = 2 ClF ₃ : Central atom Cl has 7 valence electrons. Shared = 3. Lone pairs = 7 - 3 2 = 2 XeF ₄ : Central atom Xe has 8 valence electrons. Shared = 4. Lone pairs = 8 - 4 2 = 2 Option 2: NH ₃ : Central atom N has 5 valence electrons. Shared = 3. Lone pairs = 5 - 3 2 = 1 SF ₄ : C