Question

The electronic configuration of an element B is 2, 8, 7 and it forms an ionic compound AB,with another element A. What is the valency of element A?​

Answer 1

Answer:

Since electronic configuration of B is 2,8,7 So ,

Valency of B is -1

So Valency of A is 1

It may be metal of Valency 1

Answer 2

Answer:

chlorine is 2,8,7electronic configuration is need one electron to complete last orbit so element A is valency 1