tentukan bilangan oksidasi masing masing unsur dalam senyawa berikut: NH3, CF4, CHCI3, O2F2, KO2, CaH2, BaO2, Fe2S3, CU2O, N2O4, CaO, SnO

1. NH3, N = -3, H = +1
2. CF4, C = +4, F = -1
3. CHCI3, C = +2, H = +1, Cl = -1
4. O2F2, O = +1, F = -1
5. KO2, K = +1, O = -1/2
6.  CaH2, Ca = -2, H = +1
7. BaO2, Ba = +4, O = -2
8. Fe2S3, Fe = +3, S = -2
9. CU2O, Cu = +1, O = -2
10 N2O4, N = +4, O = -2
11. CaO, Ca = +2, O = -2
12. SnO, Sn = +2, O = -2

NH3 =H=+1.3 +=3 jadi nilai N=-3
CF4= C=+2.4=+8 jadi nilai C=-8
CHCL3+ H= +1, Cl=-1.3=-3 jadi nilai C=+2
O2F2= nilai F2=+4
KO2=K=+4 O2=-4
CaH2= Ca=-2 H2==1.2=2
BaO2=Ba=+4 O2=-2.2=-4
Fe2S3=Fe2=-3 S3=+2