The value of `DeltaH_("transition")` of C (graphite) `to` C (diamond) is 1.9 kJ/mol at `25^(@)` C entropy of graphite is higher than entropy of diamond. This implies that:

Options

A. C(diamond) is more thermodyanically stable than C (graphite) at `25^(@)` C
B. C(graphite) is more thermodyanically stable than C (diamond) at `25^(@)` C
C. Diamond will provide more heat on complete combustion at `25^(@)` C
D. `DeltaG_("transition")` of C (diamond) `to C` (graphite) is `-ve`.

Explanation

To analyze the transition of carbon from graphite to diamond and determine the implications of the given data, we can follow these steps:

### Step 1: Understand the Given Data
We know that the enthalpy change (ΔH) for the transition from graphite to diamond is +1.9 kJ/mol at 25°C. This positive value indicates that the transition requires energy input, suggesting that graphite is more stable than diamond at this temperature.

**Hint:** A positive ΔH indicates that the process is endothermic, meaning energy is absorbed.

### Step 2: Compare the Entropies
We are also informed that the entropy (S) of graphite is higher than that of diamond. This means that graphite has more disorder compared to diamond, which is a more ordered structure.

**Hint:** Higher entropy indicates greater disorder; thus, a substance with higher entropy is generally less stable.

### Step 3: Analyze Thermodynamic Stability
Since graphite has a higher entropy and the transition to diamond requires energy (positive ΔH), we can conclude that graphite is thermodynamically more stable than diamond at 25°C.

**Hint:** Thermodynamic stability can often be inferred from the sign of ΔH and the comparison of entropies.

### Step 4: Evaluate the Options
Now, we can evaluate the provided options based on our analysis:

1. **Option A:** Diamond is more thermodynamically stable than graphite. (Incorrect)
- We established that graphite is more stable.

2. **Option B:** Graphite is more thermodynamically stable than diamond. (Correct)
- This aligns with our conclusion.

3. **Option C:** Diamond will provide more heat on complete combustion. (Correct)
- Since diamond is less stable, it will release more energy upon combustion compared to graphite.

4. **Option D:** ΔG transition from diamond to graphite will be negative. (Correct)
- The transition from a less stable form (diamond) to a more stable form (graphite) is favorable and will have a negative Gibbs free energy change.

### Conclusion
The correct implications based on the provided data are options B, C, and D.

**Final Answer:** Graphite is more thermodynamically stable than diamond (Option B), diamond will provide more heat on complete combustion (Option C), and the ΔG transition from diamond to graphite will be negative (Option D).

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