MyQuestionIcon

1

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

Stoichiometry

The value of ...

Question

The value of $Δ H_{O - H}$ is $109 k c a l$ ${m o l}^{- 1}$ . The formation of one mole of water in gaseous state from $H (g)$ and $O (g)$ is accompanied by:

A

218 k c a l

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

B

- 109 k c a l

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

C

- 218 k c a l

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

D

Unpredictable

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

Open in App

Solution

The correct option is C $- 218 k c a l$
The involved reaction is,
$2 H (g) + O (g) \to H_{2} O (g)$ => $Δ H = - 2 \times Δ H_{O - H}$
Hence, formation of one mole of water in gaseous state from H(g) and O(g) is accompained by,
$Δ H = - 2 \times 109 = - 218 Kcal$
Hence, the answer is option C.

Suggest Corrections

thumbs-up

0

Similar questions

Q. The enthalpies of formation of

O H (g)

H (g)

O (g)

k J m o l^{- 1}

k J m o l^{- 1}

k J m o l^{- 1} .

The value of bond enthalpy

O - H

Q. The value of

Δ H^{o}

for the reaction

{C u}^{+} + I^{-} (g) \to C u I (g)

- 446 k J

{m o l}^{- 1}

. If the ionisation energy of

C u (g)

745 k J

{m o l}^{- 1}

and the electron affinity of

I (g)

- 295 k J

{m o l}^{- 1}

, then the value of

Δ H^{+}

for the formation of one mole of

C u I (g)

C u (g)

I (g)

Q. Compute the enthalpy of formation of liquid methyl alcohol in kJ

{m o l}^{- 1}

, using the following data. Enthalpy of vaporization of liquid

{C H}_{3} O H = 38 k J / m o l

.
Enthalphy of formation of gaseous atoms from the elements in their standard states are enthalpy of formation of gaseous atoms from the elements in their standard states are

H

\to

C

\to

O

\to

249 kJ / mol
Bond Enthalpies

C - H

\to

C - O

\to

O - H

\to

Q. The enthalpy changes at

298 K

in successive breaking of

O - H

bonds of water are

H_{2} O (g) \to H (g) + O H (g); Δ H = 498 k J

{m o l}^{- 1}

O H (g) \to H (g) + O (g); Δ H = 428 k J

{m o l}^{- 1}

The bond enthalpy of

O - H

Q. Compute the heat of formation of liquid methyl alcohol in kilojoules per mole using the following data.
The heat of vaporisation of liquid methyl alcohol =

38 k J / m o l

.
The heats of formation of gaseous atoms from the elements is their standard states:

H, 218 k J / m o l

C, 713 k J / m o l

O, 249 k J / m o l

.
Average bond energies:

C - H = 415 k J / m o l

C - O = 365 k J / m o l

O - H = 463 k J / m o l

.

View More

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Stoichiometry of a Chemical Reaction

CHEMISTRY

Watch in App

explore_more_icon

Explore more

Standard XII Chemistry

Join BYJU'S Learning Program

CrossIcon