Question

Question 44 (e)
Atomic number of a few elements are given below 10, 20, 7, 14. Determine the valency of these elements.

Answer 1

Neon has atomic number 10. Its electronic configuration is 2, 8. Since its outermost shell is completely filled, its valency is 0.

Calcium has atomic number 20. Its electronic configuration is 2, 8, 8, 2. It has 2 valence electrons in its outermost shell. So, its valency is 2.

Nitrogen has atomic number 7. Its electronic configuration is 2, 5. It has 5 valence electrons in its outermost shell. So, its valency is 8 - 2 = 3.

Silicon has atomic number 14. Its electronic configuration is 2, 8, 4. It has 4 valence electrons in its outermost shell. So, its valency is 4.