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Enthalpy change for the reaction, 4H(g) ...

Enthalpy change for the reaction, `4H(g) to 2H_(2)(g)` is `-869.5kJ`. The dissociation energy of H-H bond is-

A

`-434.8kJ`

B

`-869.6kJ`

C

`+434.8kJ`

D

`+217.4kJ`

Text Solution

Verified by Experts

The correct Answer is:
C
We know, bond formation enthalpy `=(-)xx`bond dissociation enthalpy. Now, bond formation enthalpy for 2 mol H-H bonds=-869 kJ.
`therefore`Bond dissociation enthalpy for H-H bond
`=(1)/(2)xx869=434.5 kJ*mol^(-1)`
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