What is the enthalpy change for the given reaction, if enthalpies of formation of Al2O3 and Fe2O3 are -1670 kj mol-1 and -834 kj mol-1 respectively? Fe2O3 + 2Al → Al2O3+2Fe

Question

What is the enthalpy change for the given reaction, if enthalpies of formation of Al2O3 and Fe2O3 are -1670 kj mol-1 and -834 kj mol-1 respectively? Fe2O3 + 2Al → Al2O3+2Fe (A) -836 kj mol-1 (B) + 836 kj mol-1 (C) - 424 kj mol-1 (D) + 424 kj mol-1

Tardigrade Admin · Accepted Answer

Δ H = Sigma Δ HP - Sigma Δ HR = -1670 - (-834) = -836 kj mol-1

Q. What is the enthalpy change for the given reaction, if enthalpies of formation of $A l_{2} O_{3}$ and $F e_{2} O_{3}$ are $- 1670 kj m o l^{- 1}$ and $- 834 kj m o l^{- 1}$ respectively?
$F e_{2} O_{3} + 2 A l \to A l_{2} O_{3} + 2 F e$

$- 836 kj m o l^{- 1}$

$+ 836 kj m o l^{- 1}$

$- 424 kj m o l^{- 1}$

$+ 424 kj m o l^{- 1}$

$Δ H = Σ Δ H_{P} - Σ Δ H_{R}$
$= - 1670 - (- 834) = - 836 kj m o l^{- 1}$

Q. What is the enthalpy change for the given reaction, if enthalpies of formation of Al2​O3​ and Fe2​O3​ are −1670kjmol−1 and −834kjmol−1 respectively? Fe2​O3​+2Al→Al2​O3​+2Fe

−836kjmol−1

+836kjmol−1

−424kjmol−1

+424kjmol−1