Atomic Weight of Some Elements Important in Medicine

Element

Symbol

Atomic Weight*

Hydrogen

H

1

Carbon

C

12

Nitrogen

N

14

Oxygen

O

16

Sodium

Na

23

Magnesium

Mg

24

Phosphorus

P

31

Chlorine

Cl

35.5

Potassium

K

39

Calcium

Ca

40

*Approximate.