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18g of water is takento prepare the tea....

18g of water is takento prepare the tea. Find out the internal energy of vaporisation at `100^(@)`C. `(Delta_(vap)H` for water at 373 K 373 K is `40.66kJ mol^(-1))`

A

`37.56kJmol^(-1)`

B

`-37.56kJmol^(-1)`

C

`43.76kJmol^(-1)`

D

`3-43.76kJmol^(-1)`

Text Solution

Verified by Experts

The correct Answer is:
A
18g water=mol water
`H_(2)O(l)hArrH_(2)O(g)`
`DeltaH=DeltaE+Deltan_(g)RT`
`40.66=DeltaE+(1xx8.314xx373)/(1000)`
`DeltaE=40.66-3.1`
`DeltaE=+2xx(2)-(3)`
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