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The enthalpy of vaporization of liquid w...

The enthalpy of vaporization of liquid water using the data :
(i) `H_(2)(g)+((1)/(2))O_(2)(g)rarrH_(2)(O)(l)`
`DeltaH=-"285.77 kJ/mol"`
(ii). `H_(2)(g)+((1)/(2))O_(2)(g)rarr H_(2)O(g)`,
`DeltaH=-"241.84 kJ/mol in kJ/mol is "`

A

`+43.93` KJ `mol^(-1)`

B

`-43.93` KJ `mol^(-1)`

C

`+527.61` KJ `mol^(-1)`

D

`-527.61` KJ `mol^(-1)`

Text Solution

Verified by Experts

The correct Answer is:
A
`H_(2)O_((l))rarr H_(2)O_((g)) , Delta H_("Vap.")= ?`
Desired equation = eq(ii) - eq(i)
`Delta H_("Vap.") =(-241.84)-(-285.77)`
`Delta H_("Vap.")=+43.93 KJ mol^(-1)`
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