question_answer 22)

Define valency by taking examples of silicon and oxygen.

Answer:

The number of electrons gained, lost or shared so as to complete the octet of electrons in valence shell is called valency.   Valency of silicon: It has electronic configuration → 2,8.4   Thus, 4 electrons are shared with other atoms to complete the octet and so its valency = 4 Valency of oxygen : It has electronic configuration →2,6   Thus, It will gain 2 electrons to complete its octet. So its valency = 2