Ta có: $n_{C}=0,5(mol);n_{S}=0,25(mol)$
$C+O_2\rightarrow CO_2$
$S+O_2\rightarrow SO_2$
Suy ra $n_{O_2}=0,75(mol)\Rightarrow m_{O_2}=24(g)$
mC = 6.67*90% = 6(g)
nC = 6.003/12 = 0.5 (mol)
nS = 8/32 = 0.25 (mol )
C + O2 -to-> CO2
0.5__0.5
S + O2 -to-> SO2
0.25_0.25
mO2 = ( 0.5 + 0.25) 32 = 24 (g)