Question

Mention the atomic mass and atomic number of different elements ( first 20).....​

Answer 1

Answer:

Hydrogen- 1

Helium- 4

Lithium- 7

Beryllium- 9

Boron- 11

Carbon- 12

Nitrogen-14

Oxygen-16

Neon-20

Sodium-23

Magnesium-24

Aluminium-27

Silicon-28

Phosphorus-31

Sulphur-32

Chlorine-35.5

Argon-40

Potassium-39

Calcium-40

Answer 2

Explanation:

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