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The required heat for dissociation of 1 ...

The required heat for dissociation of 1 mole `H_(2)O` into its atoms (H and oxygen) is `Delta H_("Dissociation")`. Then calculate the bond energy of O - H bond.
`H_(2)O(g)rarr O(g)+2H(g) , Delta H_("Dissociation")`

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`H-O-H(g)rarr O(g)+2H(g), Delta H_("Dissociation")`
`because` required energy for breaking the 2 mole O - H bond `=Delta H_("Dissociation")`
`therefore` required energy for 1 mole `=(Delta H_("Dissociation"))/(2)`
`Delta H_(O-H)=(Delta H_("Dissociation"))/(2)`
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ALLEN-THERMODYNAMICS -EXERCISE -4
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  8. Assertion (A): May endothermic reactions that are not spontaneous at ...

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  9. Assertion (A): Pressure, volume, and temperature are all extensive pro...

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  11. Assertion :- At constant temp 0^(@)C and 1 atm, the change H(2)O(s)rar...

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  12. Assertion: The increase in internal energy (DeltaE) for the vaporisati...

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  13. Assertion :- Water in liquid state is more stable than ice at room tem...

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  14. Assertion :- In an isolated system the entropy increases due to sponta...

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  15. Assertion :- Entropy is always constant for a closed system. Reason ...

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  16. Assertion :- For an isolated system q is zero. Reason :- In an isola...

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  17. Assertion :- Entropy of system increases for a spontaneous reactions. ...

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  19. Assertion :- Q("Surr") is zero for adiabatic process Reason :- Final...

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