Which of the following is the correct statement

Options

A. Order of a reaction has always an integral value lt
B. Mechanism of a reactional proposed is always final
C. Zero order reactions are multi-step reactions
D. Order of reaction can be predicted even without knowing the rate law

Answer

To solve the question, we need to evaluate each of the four statements provided and determine which one is correct regarding chemical kinetics.

### Step-by-Step Solution:

1. **Evaluate the first statement**: "The order of the reaction is always an integral value."
- The order of a reaction is determined experimentally and can be a positive integer, negative integer, or even a fraction. Therefore, this statement is **incorrect**.

2. **Evaluate the second statement**: "The proposed mechanism is always final."
- Reaction mechanisms can be proposed based on experimental data, but they are subject to change as new data becomes available. Different mechanisms may be valid under different conditions. Thus, this statement is **incorrect**.

3. **Evaluate the third statement**: "Zero-order reactions are multi-steps."
- Zero-order reactions are typically elementary reactions, which means they occur in a single step. Therefore, this statement is **incorrect**.

4. **Evaluate the fourth statement**: "The order of a reaction can be predicted even without knowing the rate law."
- The order of a reaction is indeed an experimental quantity that can be determined through experiments without necessarily knowing the rate law. This statement is **correct**.

### Conclusion:
The correct statement among the options provided is: **"The order of a reaction can be predicted even without knowing the rate law."**