give the Valencis of first 20 elements?
Answers
Explanation:
The elements are ordered in the Periodic Table by their valences. But here is the rule, and the direct answer to your question:
The first column all have a valence of 1; this means, by the way, that they each have a single electron in their outer shell.
1. Hydrogen: 1 Valence Electron
2. Helium: 0 Valence Electrons (It is a noble gas--and like all other elements in column 18, all its electrons are stable.)
3. Lithium: 1 Valence Electron (again, it is in the first column.)
4. Beryllium: 2 Valence Electrons (It is in the second column.)
5. Boron: 3 Valence Electrons (It is in the third column of its row.)
6. Carbon: 4 Valence Electrons (It is in the fourth column of its row.)
7. Nitrogen: 5 Valence Electrons (It is in the fifth column.)
8. Oxygen: 6 Valence Electrons (it is in the sixth column.)
9. Fluorine: 7 Valence Electrons (it is in the seventh column.)
10. Neon: 0 Valence Electrons (Again, this is a noble gas, and is non-reactive.)
11. Sodium: 1 Valence Electron (first column.)
12. Magnesium: 2 Valence Electrons (second column.)
13. Aluminum: 3 Valence Electrons (third column.)
14. Silicon: 4 Valence Electrons (fourth column.)
15. Sulfur: 5 Valence Electrons (fifth column.)
16. Phosphorous: 6 Valence Electrons (sixth column.)
17. Chlorine: 7 Valence Electrons (sixth column.)
18. Argon: 0 Valence Electrons (a stable noble gas.)
19. Potassium: 1 Valence Electron (first column.)
20. Calcium: 2 Valence Electrons (second column.)
Answer:
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