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H(2)O(l) to H(2)(g)+(1)/(2)O(2)(g) Does ...

`H_(2)O(l) to H_(2)(g)+(1)/(2)O_(2)(g)` Does the above reaction occur spontaneously at 298 K ? Given that standard enthalpy of formation of water `= -285.83 " kJ mol"^(-1)`, standard entropy of `H_(2)(g), O_(2)(g) and H_(2)O(l) ` are 130.57, 205.04 and `69.95 J. K^(-1). " mol"^(-1)` respectively.

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`Delta S^(0)= S^(0)[H_(2)(g)]+(1)/(2)S^(0)[O_(2)(g)]- S^(0)[H_(2)O(l)]`
` = (130.57+(1)/(2) xx205.04-69.95)= 163.14 J. K^(-1) " mol"^(-1)`
`Delta G^(0) = (+285.83xx10^(3) -298xx163.14) J " mol"^(-1) = + ve`
The positive value of `Delta G^(0)` indicates that the reaction cannot occur spontaneously at 298 K.
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