Δ U° of combustion of CH4(g) at certain temperature is - 393 kJ mol-1. The value of Δ H° is

Question

Δ U° of combustion of CH4(g) at certain temperature is - 393 kJ mol-1. The value of Δ H° is (A) zero (B) < Δ U° (C) > Δ U° (D) equal to Δ U°

Tardigrade Admin · Accepted Answer

The balanced equation for combustion of methane is C H 4(g) + 2 O2(g) → CO2(g) + 2H2O(l) Here, Δ ng = 1 - 3 = - 2 Δ H°= Δ U°+Δ ngRT Δ H° = -393 - 2RT ∴ Δ H° < Δ U°

Q. $Δ U^{°}$ of combustion of $C H_{4 (g)}$ at certain temperature is $- 393 k J m o l^{- 1}$ . The value of $Δ H^{°}$ is

zero

$< Δ U^{°}$

$> Δ U^{°}$

equal to $Δ U^{°}$

The balanced equation for combustion of methane is
$C H_{4 (g)} + 2 O_{2 (g)} \to C O_{2 (g)} + 2 H_{2} O_{(l)}$
Here, $Δ n_{g} = 1 - 3 = - 2$
$Δ H^{\circ} = Δ U^{\circ} + Δ n_{g} RT$
$Δ H^{\circ} = - 393 - 2 RT$
$∴ Δ H^{\circ} < Δ U^{\circ}$

Q. ΔU° of combustion of CH4(g)​ at certain temperature is −393kJmol−1. The value of ΔH° is

zero

<ΔU°

>ΔU°

equal to ΔU°

The balanced equation for combustion of methane is CH4(g)​+2O2(g)​→CO2(g)​+2H2​O(l)​ Here, Δng​=1−3=−2 ΔH∘=ΔU∘+Δng​RT ΔH∘=−393−2RT ∴ΔH∘<ΔU∘

Q. $Δ U^{°}$ of combustion of $C H_{4 (g)}$ at certain temperature is $- 393 k J m o l^{- 1}$ . The value of $Δ H^{°}$ is

$< Δ U^{°}$

$> Δ U^{°}$

equal to $Δ U^{°}$

The balanced equation for combustion of methane is
$C H_{4 (g)} + 2 O_{2 (g)} \to C O_{2 (g)} + 2 H_{2} O_{(l)}$
Here, $Δ n_{g} = 1 - 3 = - 2$
$Δ H^{\circ} = Δ U^{\circ} + Δ n_{g} RT$
$Δ H^{\circ} = - 393 - 2 RT$
$∴ Δ H^{\circ} < Δ U^{\circ}$