Which of the following statement is/are correct about order of reaction:

Options

A. order of reaction is determined experimentally
B. order of reaction can not have fractional value
C. it does not necessarily depend on stoichiometric coefficients
D. it is the sum of power of concentration terms in rate low expression

Answer

To determine which statements about the order of reaction are correct, we will analyze each statement based on our knowledge of chemical kinetics.

### Step-by-Step Solution:

1. **Understanding Order of Reaction**:
- The order of a reaction is defined as the sum of the powers of the concentration terms in the rate law expression. It is determined experimentally and reflects how the rate of reaction depends on the concentration of reactants.

2. **Evaluating the Statements**:
- **Statement 1**: "Order of reaction is determined experimentally."
- This statement is **correct**. The order of a reaction cannot be deduced from the stoichiometry of the reaction alone; it must be determined through experimental data.

- **Statement 2**: "Order of reaction cannot have fractional value."
- This statement is **incorrect**. The order of a reaction can indeed be a fractional value (e.g., 1.5, 2.5). This can occur in complex reactions where the rate does not follow simple integer stoichiometry.

- **Statement 3**: "Order of reaction does not necessarily depend on stoichiometric coefficients."
- This statement is **correct**. The order of a reaction is not always equal to the stoichiometric coefficients in the balanced equation. It is derived from the rate law, which may not reflect the stoichiometry directly.

- **Statement 4**: "The sum of the powers of concentration terms in the rate law expression is the order of reaction."
- This statement is **correct**. The order of reaction is indeed calculated as the sum of the exponents of the concentration terms in the rate law expression.

3. **Conclusion**:
- Based on the evaluations:
- Statement 1: Correct
- Statement 2: Incorrect
- Statement 3: Correct
- Statement 4: Correct
- Therefore, the correct statements about the order of reaction are 1, 3, and 4.

### Final Answer:
The correct statements about the order of reaction are:
- Statement 1: Correct
- Statement 3: Correct
- Statement 4: Correct