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Calculate enthalpy change for the change...

Calculate enthalpy change for the change `8S(g)toS_(8)(g)`, given that
`H_(2)S_(2)(g)to2H(g)+2S(g),DeltaH=239.0k"cal mol"^(-1)`
`H_(2)S(g)to2H(g)+S(g),DeltaH=175.0k"cal mol"^(-1)`

A

`+512.0` k cal

B

`-512.0` k cal

C

`508.0` kcal

D

`-508.0` kcal

Text Solution

Verified by Experts

The correct Answer is:
B
`DeltaH_(S-S)+2DeltaH_(H-S)=239" "2DeltaH_(H-S)=175`
Hence `DeltaH_(S-S)=239-175=64kcal "mol"^(-1)`
Then `DeltaH` for `8S(g)toS_(8)` is `8xx(-64)=-512` kcal
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