Answer
mass of CO2 produced = 130 kg
Step-by-step explanation
Given:
mass of C2H4 formed = 64 kg = 64000 g
mass of O2 = 142 kg = 142000 g
What we know:
Molar mass of C2H4 = 28,05 g/mol
Molar mass of O2 = 31.998 g/mol
Required: mass of CO2 produced.
Solution:
Step 1: Find the limiting reagent
C2H4:
n = m/M where n is moles, is the mass and M is the molar mass
n = 64000 g/28.05 g.mol
n = 2281.64 mol
divide by coefficient (from the equation)
n = 2281.64/1 = 2281.64 mol
O2:
n = 142000/31.998
n = 4437.8 mol
Divide by coefficient
n = 4437.8/3 = 1479.3 mol
The limiting reactant (or limiting reagent) is the reactant that gets consumed first in a chemical reaction and therefore limits how much product can be formed.
Therefore O2 is the limiting reactant, since it has less number of moles, meaning it will be consumed first in the reaction
Step 2: Use the moles of the limiting reagent to find the mass of CO2 produced.
Using the stoichiometry, the molar ratio between O2 and CO2 is 3:2
Therefore the number of moles of CO2 = 4437.8 mol x (2/3)
n of CO2 = 2958.5 mol
m = n x M
m = 2958.5 mol x 44,01 g/mol
m = 130205 g
m = 130 kg