H
1- Hydrogen
He
2- helium
Li
3- lithium
Be
4- beryllium
B
5-boron
C
6- Carbon
N
7- nitrogen
O
8- oxygen
F
9- iron
Ne
10- neon
Na
11- sodium
Mg
12- magnesium
Al
13- aluminum
Si
14- silicon
P
15- phosphorus
S
16-sulfur
Cl
17-chlorine
Ar
18- Argon
K
19- potassium
Ca
20- calcium
Ti
22- titanium
Sc
21- scandium
V
23-vanadium
Cr
24- chromium