For the reaction `I_(2(g)) hArr I_(2(s)), Delta H= -ve`. Then choose the correct statement from the following
(A) The process is spontaneous at all temperature
(B) The process is accompained by an increase in entropy
(C ) The process is accompained by a decrease in entropy
(D) The process is accompained by a decrease in enthalpy

Options

A. Only A, B and C
B. Only B and D
C. Only C and D
D. Only a, C and D

Answer

To solve the problem regarding the reaction \( I_{2(g)} \rightleftharpoons I_{2(s)} \) with a negative \( \Delta H \), we will analyze each of the given statements step by step.

### Step 1: Understanding the Reaction
The reaction involves the conversion of gaseous iodine (\( I_{2(g)} \)) to solid iodine (\( I_{2(s)} \)). This indicates a phase change from gas to solid.

**Hint**: Consider how the state of matter affects molecular arrangements and interactions.

### Step 2: Analyzing Enthalpy Change
Given that \( \Delta H \) is negative, this means that the reaction is exothermic. Energy is released when gaseous iodine transitions to solid iodine.

**Hint**: Recall that a negative \( \Delta H \) indicates that the system is losing energy.

### Step 3: Analyzing Entropy Change
When a gas condenses into a solid, the molecules become more ordered and closer together. This results in a decrease in randomness or disorder, which means that the entropy (\( \Delta S \)) of the system decreases.

**Hint**: Remember that entropy is a measure of disorder; a transition from gas to solid typically results in lower entropy.

### Step 4: Evaluating Spontaneity
For a process to be spontaneous, the change in Gibbs free energy (\( \Delta G \)) must be negative. The relationship is given by:
\[ \Delta G = \Delta H - T \Delta S \]
Since \( \Delta H \) is negative and \( \Delta S \) is also negative, the term \( T \Delta S \) will be negative as well. Therefore, the overall sign of \( \Delta G \) depends on the magnitudes of \( \Delta H \) and \( T \Delta S \).

**Hint**: Consider how temperature affects the spontaneity of the reaction.

### Step 5: Conclusion on Each Statement
- **(A)** The process is spontaneous at all temperatures: **Incorrect**. The process can only be spontaneous at lower temperatures where \( |\Delta H| > |T \Delta S| \).

- **(B)** The process is accompanied by an increase in entropy: **Incorrect**. As established, the entropy decreases.

- **(C)** The process is accompanied by a decrease in entropy: **Correct**. The transition from gas to solid results in lower entropy.

- **(D)** The process is accompanied by a decrease in enthalpy: **Correct**. A negative \( \Delta H \) indicates a decrease in enthalpy.

### Final Answer
The correct statements are **(C)** and **(D)**.