Determine the enthalpy of the reaction, C 3 H 8(g)+ H 2(g) arrow C 2 H 6(g)+ CH 4(g), at 25° C, using the given heat of combustion values under standard conditions. The standard heat of formation of C 3 H 8(g) is -103 kJ / mol.

Question

Determine the enthalpy of the reaction, C 3 H 8(g)+ H 2(g) arrow C 2 H 6(g)+ CH 4(g), at 25° C, using the given heat of combustion values under standard conditions. <img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/chemistry/9079b70eb0efd55fb8044ea7ff288745-.png" /> The standard heat of formation of C 3 H 8(g) is -103 kJ / mol. (A)  (B)  (C)  (D)

Tardigrade Admin · Accepted Answer

First we need to determine heat of combustion of

C_{3} H_{8}

.

3 C (g r) + 4 H_{2} (g) ⟶ C_{3} H_{8} (g) Δ H_{f}^{\circ} = - 103 k J

\Rightarrow - 103 k J = - 3 \times 393 - 4 \times 285.80 - Δ H_{comb}^{\circ} (C_{3} H_{8})

\Rightarrow Δ H_{comb}^{\circ} (C_{3} H_{8}) = - 2219.20 k J

\Rightarrow Δ H_{r}^{\circ} = ΣΔ H_{comb}^{\circ}

(reactants)

- ΣΔ H_{comb}^{\circ}

(products)

= - 2219.20 - 285.80 + 1560 + 890 = - 55 k J

Q. Determine the enthalpy of the reaction, C3​H8​(g)+H2​(g)→C2​H6​(g)+CH4​(g), at 25∘C, using the given heat of combustion values under standard conditions. The standard heat of formation of C3​H8​(g) is −103kJ/mol.

Q. Determine the enthalpy of the reaction,
$C_{3} H_{8} (g) + H_{2} (g) \to C_{2} H_{6} (g) + C H_{4} (g)$ , at $2 5^{\circ} C$ , using the given heat of combustion values under standard conditions.

The standard heat of formation of $C_{3} H_{8} (g)$ is $- 103 k J / m o l$ .