Question

10. How much energy is released when 6 moles of octane
is burnt in air? Given ∆H° for C2(g) H2O(g) and C 8H19 (g)
respectively are - 490
,- 240 and + 160 kJ mol:


​

Answer 1

Answer:

● Answer -

Energy released = -37.44 kJ

● Explanation -

Combustion of 6 moles of octane is given by reaction -

6C8H18 + 75O2 --> 48CO2 + 54H2O

Energy released is calculated by -

∆H(reaction) = 48 × ∆H(CO2) + 54∆H(H2O) - 6∆H(C8H18) - 75∆H(O2)

∆H(reaction) = 48 × (-490) + 54 × (-240) - 6 × (160) - 75 × 0

∆H(reaction) = -37440 J

∆H(reaction) = -37.44 kJ

Therefore, -37.44 kJ energy is released when 6 moles of octane burn in air.

Hope this helped...