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For the thermochemical equation, 2H(2(...

For the thermochemical equation,
`2H_(2(g)) + O_(2(g)) rarr 2H_(2)O_(l) , Delta H = - 571.6 kJ`
Heat of decomposition of water is :

A

`-571.6kJ`

B

`+571.6kJ`

C

`-1143.2kJ`

D

`+285.8kJ`

Text Solution

Verified by Experts

The correct Answer is:
D
`H_(2)O_(omega) rarr H_(2(g)) + (1)/(2) O_(2(g)) , Delta H = (571.6)/(2) = 285.8kJ`
Since, the forward reaction is exothermic, backward has to be endothermic.
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