Periodic table first 20

Question 1

First 20 elements with their signs and valency

Answer 1

1) Hydrogen (H) = 1
2) Helium (He) = 0
3) Lithium (Li) = 1
4) Beryllium (Be) = 2
5) Boron (B) = 3
6) Carbon (C) = 4
7) Nitrogen (N) = 3
8) Oxygen (O) = 2
9) Fluorine (F) = 1
10) Neon (Ne) = 0
11) Sodium (Na) = 1
12) Magnesium (Mg) = 2
13) Aluminium (Al) = 3
14) Silicon (Si) = 4
15) Phosphorus (P) = 3, 5
16) Sulphur (S) = 2
17) Chlorine (Cl) = 1
18) Argon (Ar) = 0
19) Potassium (K) = 1

20 ) Calcium (Ca) = 2