Question

1 to 20 elements of periodic table with its atomic number mass and valency

Answer 1

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Answer 2

First 20 elements of periodic table with its atomic number mass and valency

1. Hydrogen- Atomic number :1, valency: -1 or +1
2. Helium - Atomic number:2, valency: 0
3. Lithium - Atomic number:3, valency: +1
4. Beryllium - Atomic number: 4, valency: +2
5. Boron - Atomic number:5, valency: +3, -3
6. Carbon - Atomic number:6, valency: +2, +4
7. Nitrogen - Atomic number:7, valency: -3, -2, -1, (+1), +2, +3, +4, +5
8. Oxygen - Atomic number: 8, valency: -2
9. Fluorine - Atomic number:9, valency: -1, +1
10. Neon - Atomic number:10, valency: 0
11. Sodium - Atomic number: 11, valency: +1
12. Magnesium - Atomic number: 12, valency: +2
13. Aluminium - Atomic number: 13, valency: +3
14. Silicon - Atomic number: 14, valency: -4, (+2), +4
15. Phosphorus - Atomic number: 15, valency: -3, +1, +3, +5
16. Sulfur - Atomic number: 16, valency: -2, +2, +4, +6
17. Chlorine - Atomic number: 17, valency: -1, +1, (+2), +3, (+4), +5, +7
18. Argon - Atomic number: 18, valency: 0
19. Potassium - Atomic number: 19, valency: +1
20. Calcium - Atomic number: 20, valency: +2

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