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Chemistry · THERMODYNAMICS
हिन्दीFor the formation of ammonia from its elements: \( \text{N}_2(g) + 3\text{H}_2(g) \rightarrow 2\text{NH}_3(g) \), the value of \( \Delta H \) is \( -92.4\text{ kJ} \) at \( 27^\circ\text{C} \). The change in internal energy \( \Delta U \) is: (Take \( R = 8.314\text{ J}\cdot\text{K}^{-1}\cdot\text{mol}^{-1} \))
Correct answer · Option 4
\( -87.41\text{ kJ} \)
Explanation
\( \Delta n_g = 2 - (1 + 3) = -2 \). \( \Delta U = \Delta H - \Delta n_g RT = -92.4 - (-2 \times 8.314 \times 300 \times 10^{-3}) = -92.4 + 4.988 = -87.41\text{ kJ} \).
