Using the following equation for the combustion of octane,calculate the heat associated with the combustion of 100.0 g of octane assuming complete combustion.The molar mass of octane is 114.33 g/mole.The molar mass of oxygen is 31.9988 g/mole. 2 C₈H₁₈ + 25 O₂ → 16 CO₂ + 18 H₂O ΔH°_rxn= -11018 kJ A) -535.4 kJ B) -4819 kJ C) -602.3 kJ D) -385.5 kJ E) -11018 kJ

Question

Quizplus · Accepted Answer

First, calculate the moles of octane in 100.0 g: $100.0 \, \text{g} \div 114.33 \, \text{g/mole} = 0.8747 \, \text{moles}$. The given $\Delta H^\circ_{\text{rxn}} = -11018 \, \text{kJ}$ is for the combustion of 2 moles of octane. Therefore, for 0.8747 moles, the heat associated is $-11018 \, \text{kJ} \times \frac{0.8747}{2} = -4819 \, \text{kJ}$.

Using the Following Equation for the Combustion of Octane,calculate the Heat