OnlineCBT
Chemistry · THERMODYNAMICS
हिन्दीConsider the following statements regarding bond enthalpies and atomization enthalpies: (A) For diatomic molecules like \( \text{H}_2(g) \), the bond dissociation enthalpy is identical to the enthalpy of atomization. (B) For polyatomic molecules like \( \text{CH}_4(g) \), all four \( \text{C}-\text{H} \) bond dissociation enthalpies are experimentally identical. (C) Enthalpy of atomization of sodium metal is equal to its enthalpy of sublimation. (D) Reaction enthalpies in the gas phase can be calculated using: \( \Delta_r H^\ominus = \sum \text{bond enthalpies}_{\text{products}} - \sum \text{bond enthalpies}_{\text{reactants}} \). Choose the correct answer from the options given below:
Correct answer · Option 3
\( \text{(A)} \) and \( \text{(C)} \) only
Explanation
Statements (A) and (C) are correct. (B) is incorrect because successive bond dissociation enthalpies differ in polyatomic molecules. (D) is incorrect because \( \Delta_r H^\ominus = \sum \text{B.E.}_{\text{reactants}} - \sum \text{B.E.}_{\text{products}} \).
