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Given : H(2)(g) + (1)/(2) O(2)(g) = H(...

Given :
`H_(2)(g) + (1)/(2) O_(2)(g) = H_(2)O(g) + q_(1)`
`H_(2)(g) + (1)/(2) O_(2)(g) = H_(2)O(l) + q_(2)`
The enthalpy of vaporisation of water is equal to

A

`q_(1) + q_(2)`

B

`q_(1) - q_(2)`

C

`q_(2) - q_(1)`

D

`q_(1) q_(2)`

Text Solution

Verified by Experts

The correct Answer is:
C
(i) `H_(g) + ½ O_(2) (g) rarr H_(2)0(g) + q_(1)`
(ii) `H_(2) (g) + ½ O _(2) (g) rarr H_(2) O (l) + q_ (2)`
Subtract eq. (ii) from eq. (i).
`H_(2)O(l) rarr H_(2)O(g) + q_(1) - q_(2)`
:. `Delta H = -(q_(1) - q_(2)) = q_(2) - q_(1)`
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