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A particular reaction at 27^(@)C for whi...

A particular reaction at `27^(@)C` for which `DeltaH gt 0` and `DeltaS gt 0` is found to be non-spontaneous. The reaction may proceed spontaneously if

A

The temperature is decreased

B

The temperature is increased

C

The temperature is kept constant

D

It is carried in open vessel at `27^(@)C`

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The correct Answer is:
To solve the problem, we need to analyze the conditions under which a reaction with positive enthalpy change (ΔH > 0) and positive entropy change (ΔS > 0) can become spontaneous. We will use the Gibbs free energy equation: ### Step-by-Step Solution: 1. **Understanding Gibbs Free Energy**: The Gibbs free energy (G) is given by the equation: \[ \Delta G = \Delta H - T \Delta S \] where: - ΔG = change in Gibbs free energy - ΔH = change in enthalpy - T = temperature in Kelvin - ΔS = change in entropy 2. **Conditions for Non-Spontaneity**: For a reaction to be non-spontaneous, ΔG must be greater than zero: \[ \Delta G > 0 \] Given that ΔH > 0 and ΔS > 0, we can rewrite the equation: \[ \Delta G = \Delta H - T \Delta S > 0 \] 3. **Rearranging the Inequality**: Rearranging the inequality gives: \[ \Delta H > T \Delta S \] This means that the enthalpy change is greater than the temperature multiplied by the entropy change. 4. **Effect of Temperature**: To make the reaction spontaneous (i.e., ΔG < 0), we need: \[ \Delta H < T \Delta S \] This implies that we can achieve spontaneity by increasing the temperature (T). As T increases, the term \(T \Delta S\) will also increase, potentially surpassing ΔH. 5. **Conclusion**: Therefore, the reaction may proceed spontaneously if the temperature is increased. ### Final Answer: The reaction may proceed spontaneously if the temperature is increased. ---
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