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Calculate the standard enegry change for...

Calculate the standard enegry change for the reaction:
`OF_(2)(g) +H_(2)O(g) rarr O_(2)(g) +2HF(g) at 298K`
The standard enthalpies of formation of `OF_(2)(g), H_(2)O(g)`, and `HF(g)` are `+20, -250`, and `-270 kJ mol^(-1)`, respectively.

A

`-31.2` KJ

B

`-21.2` KJ

C

`-11.2` KJ

D

`+ 41.2` KJ

Text Solution

Verified by Experts

`Delta H^(0) = sum Delta H_(f"(products)") ^(@) - sum Delta H_(f"(product)")^(@)`
`= [Delta H_(f (H_(2)O))^(0) + Delta H_(f (CO))^(0) ] - [Delta H_(f (CO_(2))^(0) + Delta H_(f (H_(2))^(0)]`
`Delta H^(@) = [-241.8 - 110.5] - [-393.5 + 0]`
`=-352.3 + 393 . 5 = + 41.2 KJ`
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