The standard enthalpy of combustion at 25° C of hydrogen, cyclohexene ( C 6 H 10) and cyclohexane ( C 6 H 12) are -241, -3800 and -3920 kJ / mol respectively. Calculate the heat of hydrogenation of cyclohexene.

Question

The standard enthalpy of combustion at 25° C of hydrogen, cyclohexene ( C 6 H 10) and cyclohexane ( C 6 H 12) are -241, -3800 and -3920 kJ / mol respectively. Calculate the heat of hydrogenation of cyclohexene. (A)  (B)  (C)  (D)

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<img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/chemistry/013acc48e0bef1dc926fc8d289b88bbb-.png" /> Δ H= Sigma Δ H textcomb ° (reactants) - Sigma Δ H textcomb 1° (products) =-3800-241-(-3920) =-121 kJ / mol

Q. The standard enthalpy of combustion at $2 5^{\circ} C$ of hydrogen, cyclohexene $(C_{6} H_{10})$ and cyclohexane $(C_{6} H_{12})$ are $- 241, - 3800$ and $- 3920 k J / m o l$ respectively. Calculate the heat of hydrogenation of cyclohexene.

$Δ H = ΣΔ H_{comb}^{\circ}$ (reactants) $- ΣΔ H_{comb} 1^{\circ}$ (products)
$= - 3800 - 241 - (- 3920)$
$= - 121 k J / m o l$

Q. The standard enthalpy of combustion at 25∘C of hydrogen, cyclohexene (C6​H10​) and cyclohexane (C6​H12​) are −241,−3800 and −3920kJ/mol respectively. Calculate the heat of hydrogenation of cyclohexene.

ΔH=ΣΔHcomb ∘​ (reactants) −ΣΔHcomb ​1∘ (products) =−3800−241−(−3920) =−121kJ/mol

Q. The standard enthalpy of combustion at $2 5^{\circ} C$ of hydrogen, cyclohexene $(C_{6} H_{10})$ and cyclohexane $(C_{6} H_{12})$ are $- 241, - 3800$ and $- 3920 k J / m o l$ respectively. Calculate the heat of hydrogenation of cyclohexene.

$Δ H = ΣΔ H_{comb}^{\circ}$ (reactants) $- ΣΔ H_{comb} 1^{\circ}$ (products)
$= - 3800 - 241 - (- 3920)$
$= - 121 k J / m o l$