puritatea= masa pura/masa impura*100 => masa pura=95*227,3/100=215,935g Al pur
MAl=27g/mol
n=m/M=215,935/27=8 moli Al
2Al + Fe2O3 => Al2O3 + 2Fe
2 moli Al....................1 mol Fe2O3
8 moli Al...................x mli Fe2O3
x=8/2=
2 moli Al.........................2 moli Fe
8 moli Al........................x=8 moli Fe
MFe=56g/mol
n=m/M=>m=n*M=8*56=