Assertion. The order of a reaction can have fractional value.
Reason. The order of reaction cannot be written from the balanced equation of the reactant.

Options

A. If both assertion and reason are true and reason is the true explanation of the assertion.
B. If both assertion and reason ae true but reason is not the true explanation of the assertion.
C. If assertion is true, but reason is false.
D. If both assertion and reason are false.

Explanation

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "The order of a reaction can have a fractional value."
- This is true because the order of a reaction is determined experimentally and can indeed be a fraction, whole number, or zero. For example, in a reaction where the rate law is found to be \( \text{Rate} = k[A]^{0.5}[B]^{1} \), the order with respect to \( A \) is \( 0.5 \), which is fractional.

2. **Understanding the Reason**:
- The reason states that "The order of reaction cannot be written from the balanced equation of the reactants."
- This is also true because the stoichiometric coefficients in a balanced equation do not necessarily reflect the actual powers in the rate law. The order of a reaction is determined experimentally and may not correspond to the coefficients in the balanced equation.

3. **Evaluating the Relationship Between Assertion and Reason**:
- While both the assertion and reason are true, the reason does not provide a valid explanation for the assertion. The assertion is about the possibility of fractional orders, while the reason discusses the relationship between stoichiometry and reaction order, which does not directly explain why fractional orders can exist.

4. **Conclusion**:
- Therefore, the correct evaluation is that both the assertion and reason are true, but the reason is not the correct explanation for the assertion.

### Final Answer:
- Both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

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