For the given reactions, H 2(g)+ F 2(g) arrow 2 HF (g) ; , Δ H°=-124 kcal H 2(g) arrow 2 H (g) ; Δ H°=104 kcal F2(g) arrow 2 F(g);, Δ H°=37.8 kcal then the value of Δ H° for H (g)+ F (g) arrow HF (g) is

Question

For the given reactions, H 2(g)+ F 2(g) arrow 2 HF (g) ; , Δ H°=-124 kcal H 2(g) arrow 2 H (g) ; Δ H°=104 kcal F2(g) arrow 2 F(g);, Δ H°=37.8 kcal then the value of Δ H° for H (g)+ F (g) arrow HF (g) is (A) 142 kcal (B) -132.9 kcal (C) 132 kcal (D) 134 kcal

Tardigrade Admin · Accepted Answer

For the reaction, H 2(g)+ F 2(g) arrow 2 HF (g) ; , Δ H°=-124 kcal Δ H°= Sigma B . E . (reactants) - Sigma B . E . (products) or -124=Δ H H - H +Δ H F - F -2 Δ H H - F =104+37.8-2 Δ H H - F ∴ 2 Δ H H - F °=104+37.8+124=265.8 kcal Bond energy of H - F =(265.8/2)=132.9 kcal ∴ Δ H° for the given reaction =-132.9 kcal

Q. For the given reactions,
$H_{2 (g)} + F_{2 (g)} \to 2 H F_{(g)};, Δ H^{\circ} = - 124 k c a l$
$H_{2 (g)} \to 2 H_{(g)}; Δ H^{\circ} = 104 k c a l$
$F_{2 (g)} \to 2 F_{(g)};, Δ H^{\circ} = 37.8 k c a l$
then the value of $Δ H^{\circ}$ for $H_{(g)} + F_{(g)} \to H F_{(g)}$ is

$142 k c a l$

$- 132.9 k c a l$

$132 k c a l$

$134 k c a l$

Q. For the given reactions, H2(g)​+F2(g)​→2HF(g)​;,ΔH∘=−124kcal H2(g)​→2H(g)​;ΔH∘=104kcal F2(g)​→2F(g)​;,ΔH∘=37.8kcal then the value of ΔH∘ for H(g)​+F(g)​→HF(g)​ is

142kcal

−132.9kcal

132kcal

134kcal

Q. For the given reactions,
$H_{2 (g)} + F_{2 (g)} \to 2 H F_{(g)};, Δ H^{\circ} = - 124 k c a l$
$H_{2 (g)} \to 2 H_{(g)}; Δ H^{\circ} = 104 k c a l$
$F_{2 (g)} \to 2 F_{(g)};, Δ H^{\circ} = 37.8 k c a l$
then the value of $Δ H^{\circ}$ for $H_{(g)} + F_{(g)} \to H F_{(g)}$ is

$142 k c a l$

$- 132.9 k c a l$

$132 k c a l$

$134 k c a l$