Statement-1. The reaction of conc. `HNO_3` and conc. `H_2SO_4` on nitrobenzene gives m- dinitrobenzene.
Statement-2. The nitro group in benzene ring decreases the electron density in the benzene ring.

Options

A. Statement-1 is True, Statement-2 is True , Statement-2 is a correct explanation for Statement-1
B. Statement-1 is True, Statement-2 is True , Statement-2 is not a correct explanation for Statement-1
C. Statement- 1 is True, Statement-2 is False
D. Statement-1 is False, Statement -2 is True

Explanation

To analyze the statements provided in the question, we will break down the reasoning step by step.

### Step 1: Understanding the Reaction
The reaction involves the treatment of nitrobenzene with concentrated nitric acid (HNO3) and concentrated sulfuric acid (H2SO4). This mixture generates the nitronium ion (NO2+), which is the active electrophile in nitration reactions.

### Step 2: Identifying the Product
When nitrobenzene is nitrated, the nitronium ion can attack the benzene ring. The position of the attack is influenced by the substituents already present on the ring. Nitrobenzene has a nitro group (-NO2) attached to it, which is a deactivating and meta-directing group.

### Step 3: Directing Effects of the Nitro Group
The nitro group decreases the electron density in the benzene ring due to its strong electron-withdrawing nature. This means that the positions ortho and para to the nitro group are less electron-rich and thus less favorable for electrophilic attack compared to the meta position. Therefore, when nitrating nitrobenzene, the major product is m-dinitrobenzene.

### Step 4: Conclusion
Based on the above analysis:
- **Statement 1** is true: The reaction of concentrated HNO3 and H2SO4 on nitrobenzene does indeed yield m-dinitrobenzene.
- **Statement 2** is also true: The nitro group decreases the electron density in the benzene ring, making it a meta-directing group.

### Final Answer
Both statements are true.

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