ad yg bisa menjawab?

1. Lambang atom = Cl
Nomor atom = 53.5
Nomor massa =71

2. Lambang = O
nomor Atom = 8
Nomor massa =16

3. Lambang = H
no. atom = 1
No.massa =1

4. Lambang = Fe
Nomor atom = 26
Nomor massa = 56