HOOC-COOH + 5[O]-->2CO2+H2O
2KMnO4+3H2SO4-->K2SO4+2MnSO4+3H2O+5[O]
Concentratia molara=n/V=> n=V*CM=0,5*1=0,5 moli KMnO4
2 moli KMnO4.......1 mol HOOC-COOH
0,5 moli KMnO4.....x==> x=0,25 moli HOOC-COOH
M C2H2O4=90 g/mol
m=n*M=90*0,25=22,5 g HOOC-COOH
Acum mi-am amintit, imi cer scuze.