Question

write the symbol and valency of elements from atomic number 1 to 18​

Answer 1

Answer:

hydrogen-1

helium-0

lithium-1

berilium-2

boron-3

carbon-4

nitrogen-3

o-2

f-1

ne-0

na-1

mg-2

al-3

si-4

ph-3

s-2

cl-1

ar-0

Answer 2

Answer:

1. H ( hydrogen ) +1 ( valency )
2. He ( helium ) 0 ( valency )
3. Li ( lithium ) +1
4. Be ( beryllium ) +2
5. B ( boron ) +3
6. C ( carbon ) +4 or -4
7. N ( nitrogen ) -3
8. O ( oxygen ) -2
9. F ( fluorine ) -1
10. Ne ( neon ) 0
11. Na ( sodium ) +1
12. Mg ( magnesium ) +2
13. Al ( aluminium ) +3
14. Si ( silicon ) +4 or -4
15. P ( phosphorus ) -3
16. S ( sulfur ) -2
17. Cl ( chlorine ) -1
18. Ar ( argon )  0

Explanation: