Answer to Question #26175 in Inorganic Chemistry for aakash choudhary

Question

Why is BiH2 the strongest reducing agent among all the hydrides of group 15 elements?

Answer 1

The 15 group or nitrogen family consists of nitrogen, phosphorus, arsenic, antimony and bismuth. As you move down the nitrogen family: atomic radius increases, ionic radius increases, ionization energy decreases, and electronegativity decreases. Nitrogen and phosphorus are nonmetals. Arsenic and antimony are metalloids. Bismuth is a metal and this is cause the main difference in behavior in comparison to nitrogen, phosphorus, arsenic and antimony. BiH₂ has ionic bond between H and Bi, while other elements have covalent, where interaction forces are higher. It means that BiH₂ is capable to breaking bond more easy than other and that's why BiH₂ is the strongest reducing agent in nitrogen family.