Which set contains only covalently bonded molecules? — Chemical Bonding Chemistry Question

💡 Solution & Explanation

Step 1: Evaluate the type of bonding present in each chemical species in the given sets. Step 2: NH4Br is an ionic salt composed of ammonium and bromide ions. NaI is a highly ionic alkali halide salt. Al is a metal with metallic bonding. Step 3: In the set BCl3, SiCl4, and PCl3, all compounds are molecular substances formed between non-metals held together entirely by covalent bonds. This matches option (a).