`CO_(2)+H_(2)Otounderset("Carbonic acid")(H_(2)CO_(3))`
Which one is incorrect about the above reaction?

Options

A. Without enzyme, the rate of H,Coformation is 200 molecules per hour
B. When carbonic anhydrase catalyses the same reaction, there is no change in the rate of `H_(2)CO_(3)` formation
C. The reaction catalysed by the enzyme shows speeds with about 600,000 molecules being formed / sec. (10 million times more rate)
D. The enzymes occurs in cytoplasm of certain cells

Answer

To determine which statement is incorrect about the reaction of carbon dioxide (CO₂) with water (H₂O) to form carbonic acid (H₂CO₃), we can analyze the information provided in the video transcript step by step.

### Step 1: Identify the Reaction
The reaction in question is:
\[ \text{CO}_2 + \text{H}_2\text{O} \rightarrow \text{H}_2\text{CO}_3 \]
This indicates that carbon dioxide reacts with water to form carbonic acid.

**Hint:** Understand the basic reaction and its products.

### Step 2: Understand the Role of Carbonic Anhydrase
The video mentions carbonic anhydrase, an enzyme that catalyzes the reaction. Without this enzyme, the reaction occurs at a very slow rate (200 molecules of H₂CO₃ per hour).

**Hint:** Enzymes can significantly increase the rate of biochemical reactions.

### Step 3: Analyze the Rate of Reaction
When carbonic anhydrase is present, the rate of formation of carbonic acid increases dramatically to approximately 600,000 molecules per second. This shows that the enzyme greatly enhances the reaction rate.

**Hint:** Compare the rates of reaction with and without the enzyme.

### Step 4: Identify the Incorrect Statement
The video states that one of the statements is incorrect: "When carbonic anhydrase catalyzes the same reaction, there is no change in the rate of H₂CO₃ formation." This is incorrect because the presence of carbonic anhydrase increases the rate of formation significantly.

**Hint:** Look for statements that contradict the established facts about enzyme activity.

### Step 5: Conclusion
The incorrect statement regarding the reaction of CO₂ with H₂O to form carbonic acid is the one that claims there is no change in the rate of H₂CO₃ formation when carbonic anhydrase is present.

**Final Answer:** The incorrect statement is that "when carbonic anhydrase catalyzes the same reaction, there is no change in the rate of H₂CO₃ formation."

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