The bond energies of$C\equiv C$, C-H, H-H and C=C are 198, 98, 103 and145 kcal respectively. The enthalpy change of the reaction $HC\equiv CH+{H}_{2}\to {C}_{2}{H}_{4}$ is

1. 48 kcal

2. 96 kcal

3. -40 kcal

4. -152 kcal

Concept Videos :-

#4 | Heat
#26 | Entropy
#29 | Entropy Change Calculation: Case II, III & IV

Concept Questions :-

Enthalpy and It's Type

The enthalpy change for the given reaction is calculated by considering the number of the various bonds broken in the reactants and the number of new bonds formed in the products.

Difficulty Level:

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