Amongst the following trihalide, which one is least basic? — Chemical Bonding Chemistry Question

💡 Solution & Explanation

Step 1: The basicity of nitrogen trihalides (NX_3) is determined by the availability of the lone pair on the Nitrogen atom to be donated to a Lewis acid. Step 2: Fluorine is the most electronegative halogen (E.N. = 4.0), which strongly withdraws electron density from Nitrogen via the inductive effect. This significantly reduces the electron density of the lone pair on Nitrogen, making it the least available for donation. Step 3: Consequently, NF_3 is the least basic trihalide. Therefore, the correct option is (a).