Question

Why anhydrous HCl is a poor conductor while aqueous HCl is an excellent conductor ?

Answer 1

Because anhydrous HCL is a poor conductor because it doesn't have free ions or ions of H+ is not present..

And

Aqueous solution of HCL is excellent conductor because it has H+ ions present in water..

Answer 2

Anhydrous HCL do not have water molecules and we know that acid show acidic behaviour in aqueous solution .It gives H+ ion in water and make it conducting .So aqueous HCL is execellent conductor as compared to anhydrous HCL.