A and B are two elements with atomic numbers 9 and 17 respectively. Explain why the element A is a more powerful oxidisng agent than the element B.

Explanation

Electronic configuration of `""_(9)A:1s^(2)2s^(2)2p^(5)`, electronic configuration of `""_(17)B:1s^(2)2s^(2)2p^(6)3s^(2)3p^(5)`. Both A and B can accept 1 electron to form theh anions of `A^(-) and LB^(-)` having inert gas electronic configuration. however, the anions `A^(-)` is more stable than `B^(-)` because of the smaller atomic size of A. so A is a stronger oxidising agent than B.