Hey,
1) We balance the equation of the reaction, that to say :
2C₄H₁₀ + 13O₂ → 8CO₂ + 10H₂O
2) Calculating the molar mass of simple butane :
M(C₄H₁₀) = 4M(C) + 10M(H)
3) Let us calculate the quantity of material corresponding to the mass of simple butane :
n(C₄H₁₀) = m/M
4) Determining the progress maximal x of the reaction,
xmax = n(C₄H₁₀)/2
5) If the reagents are supplied in a stoichiometric quantity, and the combustion is complete, then :
n(CO₂) = xmax x 8
m(CO₂) = M(CO₂) x n(CO₂)