Respostas

2013-11-20T01:17:45-02:00
H4p2o7: 4.1+ 2Nox - 7.2= 0__ Nox do P= 5

2.3= +6 - 24 = (+6-24)/3=0 
+3= +6 
Al2 (SO4)3 

 +5 +6