Which of the natural process is spontaneous

Options

A. Formation of curd from milk after doing initation
B. `"Conversion of C (graphite)" rarr "C(Diamond) at" 25^(@)C` and latex.
C. Formation of `H_(2)(g)` and `O_(2)`(g)` from H_(2)O(l)`
D. Formation of `CrO_(5)` from `H_(2)O_(2)` and `K_(2)Cr_(2)O_(7)` in basic medium

Answer

To determine which of the given natural processes is spontaneous, we will analyze each option based on the principles of thermodynamics.

### Step-by-Step Solution:

1. **Analyze Option A: Formation of curd from milk after doing initiation.**
- The process of curd formation involves the action of bacteria on milk, which converts lactose into lactic acid. This process occurs naturally after the initial initiation (adding a starter culture).
- **Conclusion:** This process is spontaneous because it occurs naturally under the right conditions without requiring continuous external energy input after initiation.

2. **Analyze Option B: Conversion of graphite into diamond at 25 degrees Celsius and 1 atmosphere pressure.**
- The conversion of graphite to diamond is a thermodynamically unfavorable process at standard conditions (25°C and 1 atm) because it requires extremely high pressure (around 150,000 atm) to occur.
- **Conclusion:** This process is not spontaneous under the given conditions.

3. **Analyze Option C: Formation of hydrogen and oxygen gas from water (liquid state).**
- The dissociation of water into hydrogen and oxygen gas is not a spontaneous process under normal conditions. It requires an external energy source, such as electrolysis, to break the bonds in water.
- **Conclusion:** This process is not spontaneous because it requires an external electric discharge.

4. **Analyze Option D: Formation of CrO5 from H2O2 and K2Cr2O7 in basic medium.**
- The reaction between hydrogen peroxide (H2O2) and potassium dichromate (K2Cr2O7) to form CrO5 occurs only in an acidified solution, not in basic conditions. Therefore, it cannot proceed spontaneously in basic medium.
- **Conclusion:** This process is not spontaneous in the given conditions.

### Final Answer:
The only spontaneous process among the options provided is **Option A: Formation of curd from milk after doing initiation.**

---