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Chemistry · CHEMICAL BONDING AND MOLECULAR STRUCTURE
हिन्दीThe bond dissociation enthalpies for breaking the two successive \( \text{O}-\text{H} \) bonds in gaseous water are \( 502\text{ kJ mol}^{-1} \) and \( 427\text{ kJ mol}^{-1} \), respectively. Calculate the total energy required to completely atomize \( 3.6\text{ g} \) of gaseous \( \text{H}_2\text{O} \) into gaseous \( \text{H} \) and \( \text{O} \) atoms.
Correct answer · Option 1
\( 185.8\text{ kJ} \)
Explanation
Total enthalpy to break both O-H bonds in 1 mol of H2O is \( 502 + 427 = 929\text{ kJ mol}^{-1} \). For \( 3.6\text{ g} \) (\( 0.2\text{ mol} \)), required energy = \( 0.2 \times 929 = 185.8\text{ kJ} \).
