Question

Problem Page

Gaseous methane

CH4

reacts with gaseous oxygen gas

O2

to produce gaseous carbon dioxide

CO2

and gaseous water

H2O

. If

4.66g

of carbon dioxide is produced from the reaction of

8.66g

of methane and

24.2g

of oxygen gas, calculate the percent yield of carbon dioxide.

Be sure your answer has the correct number of significant digits in it.

Answer 1

number of mole = (given mass)/(molar mass)
molar mass of CH4 = 16 g/mol
molar mass of O2 = 32 g/mol
number of mole of CH4 = 8.66/16
= 0.54 mole
number of mole of O2 = 24.2/32
= 0.76 mole
reaction taking place is
CH4 + 2O2 -- > CO2 + 2H20
according to reaction
1 mol of CH4 required 2 mol of O2
0.54 mol of CH4 required (2*0.54) mol of O2
0.54 mol of CH4 required 1.08 mol of O2
but we have only 0.76 mol of O2
so, O2 is limiting reagent

now, again according to reaction
2 mol of O2 give 1 mol CO2
1 mol of O2 give 1/2 mol CO2
0.76 mol of O2 give (1/2)*0.76 mol CO2
number of mole of CO2 produce = 0.38 mole
mass of CO2 produce = (number of mole of CO2)*(molar mass of CO2)
molar mass of CO2 = 44 g/mol
mass of CO2 produce = (0.38*44) g
= 16.7 g

%yield = {(actual yield of CO2)/(therotical yield)}*100
= (4.66/16.7)*100
= 27.9 %

Answer : 27.9%