C+CuO--->CO+Cu
2 moli CuO=> 2 moli C. numarul de moli=masa/masa molara=> masa C=moli*miu= 2*12=24g C pur.
100%-40%=60% ( C pur)
60/100*x=24g (x fiind masa totala de C)=>x=40g.
2 moli CuO=>2 moli CO degajati. numarul de moli=V/ Vmolar=> V=moli*Vm=> V CO=2*22.4=44.8 L CO degajati