nKMnO4 = 15.8/158 = 0.1 (mol)
2KMnO4 -to-> K2MnO4 + MnO2 + O2
0.1__________________________0.05
VO2 = 0.05*22.4 = 1.12 (l)
nFe = 5.6/56 = 0.1 (mol)
3Fe + 2O2 -to-> Fe3O4
0.075__0.05_____0.025
mFe3O4 = 0.025*232 = 5.8 (g)
Theo gt ta có: $n_{KMnO_4}=0,1(mol)$
a, $2KMnO_4\rightarrow K_2MnO_4+MnO_2+O_2$
b, Ta có: $n_{O_2}=0,05(mol)\Rightarrow V_{O_2}=1,12(l)$
c, Theo gt ta có: $n_{Fe}=0,1(mol)$
$3Fe+2O_2\rightarrow Fe_3O_4$
Ta có: $n_{Fe_3O_4}=0,025(mol)\Rightarrow m_{Fe_3O_4}=5,8(g)$
nKMnO4 = 15.8/158 = 0.1 (mol) 2KMnO4 -to-> K2MnO4 + MnO2 + O2 0.1__________________________0.05 VO2 = 0.05*22.4 = 1.12 (l) nFe = 5.6/56 = 0.1 (mol) 3Fe + 2O2 -to-> Fe3O4 0.075__0.05_____0.025 mFe3O4 = 0.025*232 = 5.8 (g)