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The following are the heats of reactions...

The following are the heats of reactions -
(i) `Delta H_(f)^(@)` of `H_(2)O_((l))=-68.3 "K cal mol"^(-1)`
(ii) `Delta H_("comb.")^(@)` of `C_(2)H_(2)=-337.2 "K cal mol"^(-1)`
(iii) `Delta H_("comb.")^(@)` of `C_(2)H_(4)=-363.7 "K cal mol"^(-1)`
Then heat change for the reaction `C_(2)H_(2)+H_(2)rarr C_(2)H_(4)` is -

A

`-716.1 kcal`

B

`+337.2 kcal`

C

`-41.8 kcal`

D

`-579.5 kcal`

Text Solution

Verified by Experts

The correct Answer is:
C
Add eqn. `(i)` and `(iii)` and subtract equation `(ii)`
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DINESH PUBLICATION-CHEMICAL THERMODYNAMICS AND CHEMICAL ENERGETICS -Exercise
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  6. The equilibrium constant for a reaction is 10. What will be the value ...

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  7. One mole of an ideal gas expanded freely and isothermally at 300 K fro...

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  8. For the reaction C(6)H(12)(l)+9O(2)(g)to6H(2)O(l)+6CO(2)(g) , DeltaH...

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  9. Given that the data for neutralization of weak acid (HA) and strong ac...

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  13. Calculate the work done when 1.0 mol of water at 373K vaporises agains...

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  14. The maximum efficiency of heat engine operating between 100 ^(@) and 2...

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  15. A gas absorbs 250 J of heat and expands from 1 litre to 10 litres agai...

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  16. Which of the following value of DeltaH(f)^(@) represent that the produ...

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  17. The enthalpies of formation of N(2)O and NO are respectively 82 and 90...

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  18. The value of DeltaH(O-H) is 109 kcal mol^(-1). Then formation of one m...

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  20. For a system in equilibrium, DeltaG=0, under conditions of constant

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