Rate of reaction can be expressed as
I the rate of decrease in concentration of any of the reactants.
II the rate of increase in concentration of any of the products
which od the above mentioned statement is correct choose the correct option.

Options

A. Only I
B. Only II
C. Both I and II
D. Neither I nor II

Answer

To solve the question regarding the rate of reaction and the correct statements about it, we can follow these steps:

### Step 1: Understand the Concept of Rate of Reaction
The rate of a chemical reaction is defined as the change in concentration of reactants or products over a specific period of time.

### Step 2: Analyze the Statements
- **Statement I**: The rate of reaction can be expressed as the rate of decrease in concentration of any of the reactants.
- **Statement II**: The rate of reaction can be expressed as the rate of increase in concentration of any of the products.

### Step 3: Evaluate Statement I
When a reaction occurs, the reactants are consumed, which leads to a decrease in their concentration. Therefore, it is correct to express the rate of reaction as the rate of decrease in concentration of any of the reactants.

### Step 4: Evaluate Statement II
As the reaction proceeds, products are formed, leading to an increase in their concentration. Thus, it is also correct to express the rate of reaction as the rate of increase in concentration of any of the products.

### Step 5: Conclusion
Both statements are correct. The rate of reaction can be expressed in terms of the decrease in concentration of reactants or the increase in concentration of products.

### Final Answer
Both Statement I and Statement II are correct.

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