Question

illustrate stepwise how will you find the velency of following elements. chlorine, potessoum,phophoruse

Answer 1

Chlorine : First examine it's atomic number which is in this case 17.Now as you know put electrons in their shells.In K-2...L-8...and M-7.So it will be easier to gain one electron rather losing up 7.
So valency of chlorine is 1.
Similarly valency of potassium is 1.
and valency of 3.