Question

What volume of oxygen at STP is required to affect the
combustion of 11 litres of ethylene [C,H,) at 273°C and
380 mm of Hg pressure?
CH4 + 302 → 2002 + 2H20​

Answer 1

Answer:

let no. of mole of C2H4 is n

pressure = 380/760 atm = 1/2 atm

T = 273+273 = 546K

V = 11 L

R = 0.0821

apply 

PV = nRT

11/2= n*0.0821*546

n = 0.123 mole

for one mole of combustion of C2H4 3mole of O2 is required

so for 

0.123 mole = 3*0.123 mole  O2 required

               = 0.369mole

volume of one mole gas at stp = 22.4L

volume of 0.369 mole O2 at stp = 22.4*0.369 = 8.27L