a ) C + o2 --> Co2
x ---> x
S + o2 --> So2
y --> y
b) Goi so mol C la : x so mol S la :y
ta co hpt : 12x+32y = 2.8
x+y = 0.15 (so mol O2) => x =0.1 mol y = 0.05 mol
m C = 0.1*12 = 1.2 g mS = 0.05*32 = 1.6 g
c ) % C = (0.1*12) *100 / 2.8= 42.85 % % S = 100% - 42.85 % =57.15 %