\(n_{Fe_3O_4}=\dfrac{m}{M}=\dfrac{6,96}{56\cdot3+16\cdot4}=0,03\left(mol\right)\\ PTHH;3Fe+2O_2-^{t^o}>Fe_3O_4\)
tỉ lệ: 3 : 2 : 1
n(mol) 0,09<-----0,06<---0,03
\(m_{Fe}=n\cdot M=0,09\cdot56=5,04\left(g\right)\\ V_{O_2\left(dktc\right)}=n\cdot22,4=0,06\cdot22,4=1,344\left(l\right)\)
a) $3Fe + 2O_2 \xrightarrow{t^o} Fe_3O_4$
b) $n_{Fe_3O_4} = \dfrac{6,96}{232} = 0,3(mol)$
Theo PTHH :
$n_{Fe} = 3n_{Fe_3O_4} = 0,9(mol) \Rightarrow m_{Fe} = 0,9.56 = 50,4(gam)$
$n_{O_2} = 2n_{Fe_3O_4} = 0,6(mol) \Rightarrow V_{O_2} = 0,6.22,4 = 13,44(lít)$