Periodic Table First 20 Elements Atomic and Mass

Hydrogen - Atomic Number

1

Hydrogen - Mass Number

1

Helium - Atomic Number

2

Helium - Mass Number

4

Lithium - Atomic Number

3

Lithium - Mass Number

7

Beryllium - Atomic Number

4

Beryllium - Mass Number

9

Boron - Atomic Number

5

Boron - Mass Number

11

Carbon - Atomic Number

6

Carbon - Mass Number

12

Nitrogen - Atomic Number

7

Nitrogen - Mass Number

14

Oxygen - Atomic Number

8

Oxygen - Mass Number

16

Fluorine - Atomic Number

9

Fluorine - Mass Number

19

Neon - Atomic Number

10

Neon - Mass Number

20

Sodium - Atomic Number

11

Sodium - Mass Number

23

Magnesium - Atomic Number

12

Magnesium - Mass Number

24

Aluminum - Atomic Number

13

Aluminum - Mass Number

27

Silicon - Atomic Number

14

Silicon - Mass Number

28

Phosphorus - Atomic Number

15

Phosphorus - Mass Number

31

Sulfur - Atomic Number

16

Sulfur - Mass Number

32

Chlorine - Atomic Number

17

Chlorine - Mass Number

35

Argon - Atomic Number

18

Argon - Mass Number

40

Potassium - Atomic Number

19

Potassium - Mass Number

39

Calcium - Atomic Number

20

Calcium - Mass Number

40