1.

On the basis of the following thermochemical data (Delta f G^(@)H_((aq))^(+)=0) H_(2)O(l) rarr H^(+)(aq)+OH^(-)(aq), DeltaH=57.32 kJ H_(2)(g)+1/2 O_(2)(g) rarr H_(2)O(l), DeltaH=-286.20 kJ The value of enthalpy of formation of OH^(-) ion at 25^(@)C is -

Answer»

`-228.88 kJ`
`+ 228.88 kJ`
`-343.52 kJ`
`-22.88 kJ`

Solution :`H_(2)O(L) RARR H^(+) (AQ) +OH^(-)(aq), DeltaH=57.32 kJ""`....(i)
`H_(2)(g) +1/2 O_(2)(g) rarr H_(2)O(l), DeltaH=-286.20 KJ""`.....(ii)
For the reaction
`H_(2)(g)+1/2 O_(2) (g) rarr H^(+)(aq) +OH^(-)(aq)""DeltaH=?`
By ADDING equation (i) and (ii)
`H_(2)(g)+1/2 O_(2)(g) rarr H^(+) (aq) +OH^(-) (aq)""DeltaH=57.32 kJ -286.20 kJ`
`DeltaH=-280.88" kJ/mol"`


Discussion

No Comment Found

Related InterviewSolutions