M,magnetita= 232g/mol
A,Fe=56g/mol
A,C=12g/mol
ecuatia reactiei
1mol 2mol 3mol 2mol
Fe3O4 +2C---> 3Fe + 2CO2
232g.......2x12g......3x56g.......2mol
x..............440g..............y...........z
a). z=n,CO2= 440x2/24=.........................calculeaza
b). y=m,Fe= 440x3x56/24=......................calculeaza.
c). x=m,magnetita= 440x232/24= 42533,3g pura
p/100=m,pur/m,impur
80/100= 42533,3/ m,impur......................calculeaza!