1/20
H2
3/20
F2
4/20
S8
5/20
N2
6/20
O2
7/20
I2
9/20
Br2
10/20
C2H5OH
Hint: 1 choice
11/20
P4
12/20
CH3OH
Hint: 1 choice
13/20
C6H1206
Hint: 1 choice
15/20
C12H22011
Hint: 1 choice
16/20
C3H8
Hint: 1 choice
17/20
H202
18/20
CH3COOH
Hint: 1 choice
19/20
Cl2