100g of propane is completely reacted with 1000g of oxygen. The mole fraction of carbon dioxide in the resulting mixture is x×10−2. The value of x is ......... (Nearest integer) [Atomic weight : H=1.008,C=12.00,O=16.00]
1 mole of propane reacts completely with 5 moles of oxygen to form 3 moles of carbon dioxide and 4 moles of steam. 44 g of propane = 1 mole of propane 100g of propane =
1
44
×100=2.27‌mol 32g of O2=1 mole of O2 1000g of O2=
1
32
×1000=31.25 moles ∴ 2.27 moles of propane requires 5×2.27=11.35 moles of O2 moles of CO2 formed =3×2.7=6.681 mol of CO2
‌
‌
at‌t=0
at=t
CH3CH2CH3
1
2.27‌mol
0
‌‌
+
:
5O2
5
31.25‌mol
31.25−(5×2.27)
19.90‌mol
→
3CO2
3
0
3×2.27
6.81‌mol
+
:
4H2O
4
0
4×2.27
9.08‌mol
When reaction is completed 19.90 moles of O2, 6.81 moles of CO2 and 9.08 moles of steam are left in the flask. Mole fraction of CO2=