OnlineCBT
Chemistry · THERMODYNAMICS
हिन्दीThe standard reaction enthalpy for the decomposition \( \text{CaCO}_3(s) \rightarrow \text{CaO}(s) + \text{CO}_2(g) \) is \( +178.3\text{ kJ mol}^{-1} \). The amount of heat required to decompose 25.0 g of pure \( \text{CaCO}_3(s) \) (molar mass = \( 100\text{ g mol}^{-1} \)) into \( \text{CaO}(s) \) and \( \text{CO}_2(g) \) under standard conditions is:
Correct answer · Option 1
44.58 kJ
Explanation
Moles of \( \text{CaCO}_3 = 25.0 / 100 = 0.25\text{ mol} \). Heat required = \( 0.25 \times 178.3\text{ kJ} = 44.575\text{ kJ} \approx 44.58\text{ kJ} \).
