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प्रश्न
What is the usual definition of entropy?
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उत्तर
- Entropy is a thermodynamic state function that is a measure of the randomness or disorderliness of the system.
- For a reversible change taking place at a constant temperature (T). the change in entropy
- The system is equal to heat energy absorbed or evolved (q) by the system divided by the constant temperature (T).
`Δ"S"_"sys" = "q"_"rev"/"T"`
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संबंधित प्रश्न
∆S is expected to be maximum for the reaction
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- Heat
- Temperature
- Work
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| Liquid | Boiling points (°C) | ΔH (kJ mol−1) |
| Ethanol | 78.4 | + 42.4 |
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| Liquid | Boiling points (°C) | ΔH (kJ mol−1) |
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Cyanamide (NH2CN) is completely burnt in excess oxygen in a bomb calorimeter, ΔU was found to be −742.4 kJ mol−1, calculate the enthalpy change of the reaction at 298 K.\[\ce{NH2CN_{(s)} + 3/2 O2_{(g)} -> N2_{(g)} + CO2_{(g)} + H2O_{(l)}}\] ΔH = ?
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