Answer: 2C4H10(g) + 13O2(g)----->8CO2(g) + 10H2O(g)
Explanation:
From the general formula for combustion of alkanes:
CnH2n+2 + 3n+1/2 O2------------> nCO2 + (n+1)H2O
We have:
C4H10(g) + 13/2 O2(g) ---------> 4 CO2(g) + 5H2O(g)
Now we can multiply by 2 to obtain the lowest whole number coefficients
2C4H10(g) + 13O2 (g) ---------->8CO2(g) + 10 H2O(g)
We had to multiply by two because it is the integer that will give us the lowest coefficient. Multiplying through by 2 will give the expected result.