Answer:
C3H8
Explanation:
To determine which compound will produce the largest amount of CO2 when 2.5 moles of each is burned completely in O2, we need to compare the mole ratios of the compounds and the CO2 produced in their balanced chemical equations.
The balanced chemical equations for the combustion of the compounds are:
C3H8 + 5O2 → 3CO2 + 4H2O
C4H10 + 13/2 O2 → 4CO2 + 5H2O
C8H18 + 25/2 O2 → 8CO2 + 9H2O
From these equations, we can see that 1 mole of C3H8 produces 3 moles of CO2, 1 mole of C4H10 produces 4 moles of CO2, and 1 mole of C8H18 produces 8 moles of CO2.
Therefore, when 2.5 moles of each compound are burned completely in O2, the largest amount of CO2 will be produced by C8H18, which produces 8 moles of CO2 per mole of the compound. The amount of CO2 produced by 2.5 moles of C8H18 would be 8 x 2.5 = 20 moles.
In comparison, 2.5 moles of C3H8 would produce 3 x 2.5 = 7.5 moles of CO2, and 2.5 moles of C4H10 would produce 4 x 2.5 = 10 moles of CO2.