In which of the following species central atom is NOT surrounded by exactly 8 valence electrons? — Chemical Bonding Chemistry Question

💡 Solution & Explanation

Step 1: Calculate the total number of valence electrons surrounding the central atom in each species to see if they satisfy a strict octet. Step 2: BF4^- has Boron with 4 bond pairs (8 electrons). NCl3 has Nitrogen with 3 bond pairs and 1 lone pair (8 electrons). PCl4^+ has Phosphorus with 4 bond pairs (8 electrons). Step 3: SF4 has Sulfur with 4 bond pairs and 1 lone pair, totaling 10 electrons in its valence shell. Therefore, SF4 does not contain exactly 8 valence electrons around its central atom, corresponding to option (d).