Standard molar enthalpies of formation of CaCO 3( s ) CaO ( s ) and CO 2( g ) are -1206 ⋅ 92 kJ mol -1,-635 ⋅ 09 kJ mol -1 and -393 ⋅ 51 kJ mol -1 respectively. The Δ Hr for decomposition of CaCO 3( s ) is

Question

Standard molar enthalpies of formation of CaCO 3( s ) CaO ( s ) and CO 2( g ) are -1206 ⋅ 92 kJ mol -1,-635 ⋅ 09 kJ mol -1 and -393 ⋅ 51 kJ mol -1 respectively. The Δ Hr for decomposition of CaCO 3( s ) is (A) 178.3 kJ mol-1 (B)  - 178.3 kJ mol-1 (C) 1448.5 kJ mol-1 (D)  - 1448.5 kJ mol-1

Tardigrade Admin · Accepted Answer

CaCO 3( s ) longrightarrow CaO ( s )+ CO 2( g ) Δr H° =Δf H°( CaO )+Δf H°( CO 2)-Δf H°( CaCO 3) =(-635.09)+(-393.51)-(-, 1206.92) =178 ⋅ 3 kJ mol -1

Q. Standard molar enthalpies of formation of $C a C O_{3 (s)} C a O_{(s)}$ and $C O_{2} (g)$ are $- 1206 \cdot 92 k J m o l^{- 1}, - 635 \cdot 09 k J m o l^{- 1}$ and $- 393 \cdot 51 k J m o l^{- 1}$ respectively. The $Δ H_{r}$ for decomposition of $C a C O_{3 (s)}$ is

$178.3 k J m o l^{- 1}$

$- 178.3 k J m o l^{- 1}$

$1448.5 k J m o l^{- 1}$

$- 1448.5 k J m o l^{- 1}$

$C a C O_{3 (s)} ⟶ C a O_{(s)} + C O_{2 (g)}$
$Δ_{r} H^{\circ} = Δ_{f} H^{\circ} (C a O) + Δ_{f} H^{\circ} (C O_{2}) - Δ_{f} H^{\circ} (C a C O_{3})$
$= (- 635.09) + (- 393.51) - (-, 1206.92)$
$= 178 \cdot 3 k J m o l^{- 1}$

Q. Standard molar enthalpies of formation of CaCO3(s)​CaO(s)​ and CO2​(g) are −1206⋅92kJmol−1,−635⋅09kJmol−1 and −393⋅51kJmol−1 respectively. The ΔHr​ for decomposition of CaCO3(s)​ is

178.3kJmol−1

−178.3kJmol−1

1448.5kJmol−1

−1448.5kJmol−1