- H for the reaction- OF2 - H2O - O2 - 2HF -B-E- of O - F- O - H- H - F and O - O are 44- 111- 135 and 119 kcal mol-1 respectively

The correct option is D 79 kcalFrom Hess' Law, Δ H = ∑ B.E._R ∑ B.E._P #160; #160; #160; #160; #160; #160; #160; #160; #160; ...

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Byju's Answer

Standard XII

Chemistry

Heat of Reaction

Δ H for the r...

Question

$Δ H$ for the reaction, $O F_{2} + H_{2} O \to O_{2} + 2 H F$ :(B.E. of O - F, O - H, H - F and O = O are 44, 111, 135 and 119 kcal $m o l^{- 1}$ respectively)

-222 kcal

No worries! We‘ve got your back. Try BYJU‘S free classes today!

-88 kcal

No worries! We‘ve got your back. Try BYJU‘S free classes today!

-111 kcal

No worries! We‘ve got your back. Try BYJU‘S free classes today!

-79 kcal

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Open in App

Solution

The correct option is D -79 kcal
From Hess' Law, $Δ H = \sum B . E ._{R} - \sum B . E ._{P}$
= (2 X 44 + 2 X 111) - (119 + 2 X 135)
= -79 kcal

Suggest Corrections

Similar questions

Q. Find the

Δ H

of the following reaction.

O F_{2} (g) + H_{2} O (g) ⟶ O_{2} (g) + 2 H F (g)

. Average bond energies of

O - F

O - H

O = O

and

H - F

are

44

111

118

and

135

kcal mol

^{- 1}

, respectively.

Q. Bond energy of

H - H, F - F

and

H - F

bonds are

104, 38

and

135

kcal mol

^{- 1}

respectively. Resonance energy (in

k c a l m o l^{- 1}

) in the

H - F

molecule is :

Q. The heat of formation of

C_{2} H_{5} O H (l)

- 66 k c a l m o l^{- 1}

. The heat of combustion of

C H_{3} O C H_{3} (g)

- 348 k c a l m o l^{- 1}

△ H_{f}

for

H_{2} O

and

C O_{2}

are

- 68 k c a l m o l^{- 1}

and

- 94 k c a l m o l^{- 1}

respectively.
Then, the

△ H

for reaction

C_{2} H_{5} O H (l) \to C H_{3} O C H_{3} (g)

is :

$C (s) + O_{2} (g) \to C O_{2} (g), Δ_{r} H = - 94.3 k c a l / m o l$

$C O (g) + \frac{1}{2} O_{2} (g) \to C O_{2} (g), Δ_{r} H = - 67.4 k c a l / m o l$

$O_{2} (g) \to 2 O (g), Δ_{r} H = 117.4 K c a l / m o l$

$C O (g) \to C (g) + O (g), Δ_{r} H = 230.6 K c a l / m o l$

Calculate: $Δ_{r} H f o r C (s) \to C (g) i n K c a l / m o l$

Q. Given,

C (s) + O_{2} (g) \to C O_{2} (g) Δ H = - 94.2 k c a l

H_{2} (g) + \frac{1}{2} O_{2} (g) \to H_{2} O (l) Δ H = - 68.3 k c a l

C H_{4} (g) + 2 O_{2} (g) \to C O_{2} (g) + 2 H_{2} O (l) Δ H = - 210.8 k c a l

The heat of formation of methane in kcal will be :

Join BYJU'S Learning Program

ΔH for the reaction, OF2+H2O→O2+2HF :(B.E. of O - F, O - H, H - F and O = O are 44, 111, 135 and 119 kcal mol−1 respectively)

The correct option is D -79 kcalFrom Hess' Law, ΔH=∑B.E.R−∑B.E.P = (2 X 44 + 2 X 111) - (119 + 2 X 135) = -79 kcal

$Δ H$ for the reaction, $O F_{2} + H_{2} O \to O_{2} + 2 H F$ :(B.E. of O - F, O - H, H - F and O = O are 44, 111, 135 and 119 kcal $m o l^{- 1}$ respectively)

The correct option is D -79 kcal
From Hess' Law, $Δ H = \sum B . E ._{R} - \sum B . E ._{P}$
= (2 X 44 + 2 X 111) - (119 + 2 X 135)
= -79 kcal