Which of the following sttements is//are true

Options

A. Substitution of benzene oC Curs through nucleophilic attack.
B. `AlCl_(3)` (aq). Is used as catalyst in Friedel-Crafts reaction.
C. Diphenyl methane is obtained when excess benzene is treated with dichloro methane in presence of anhydrous `AlCl_(3)`.
D. gives ortho-methyl aniline when treated with `CH_(3)Cl` in presence of `AlCl_(3)` (anhydrous)

Answer

To determine which of the statements are true, we will analyze each statement one by one.

### Step 1: Analyze the first statement
**Statement 1:** "Substitution of benzene occurs through nucleophilic attack."

- **Analysis:** Benzene is an electron-rich compound due to its delocalized pi electrons. Nucleophiles are species that seek positive charges or electron-deficient centers. Since benzene is electron-rich, it does not undergo nucleophilic substitution. Instead, it undergoes electrophilic substitution, where electrophiles (electron-seeking species) attack the benzene ring. Therefore, this statement is **false**.

### Step 2: Analyze the second statement
**Statement 2:** "AlCl3 aqueous is used as a catalyst in Friedel-Craft reactions."

- **Analysis:** Friedel-Crafts reactions, which include alkylation and acylation of benzene, require anhydrous (dry) AlCl3 as a catalyst. The presence of water (aqueous AlCl3) would lead to the formation of hydrolysis products, preventing the reaction from proceeding effectively. Therefore, this statement is also **false**.

### Step 3: Analyze the third statement
**Statement 3:** "Diphenylmethane is obtained when excess benzene is treated with dichloromethane in the presence of anhydrous AlCl3."

- **Analysis:** In the presence of anhydrous AlCl3, dichloromethane can react with excess benzene to form diphenylmethane through a Friedel-Crafts reaction. This statement is **true**.

### Step 4: Analyze the fourth statement
**Statement 4:** "Aniline gives ortho methyl aniline when treated with Cl3Cl in the presence of AlCl3."

- **Analysis:** Aniline is a basic compound and will react with Lewis acids like AlCl3 to form a salt, which prevents it from undergoing Friedel-Crafts reactions. Therefore, this statement is **false**.

### Conclusion
Based on the analysis:
- Statement 1: False
- Statement 2: False
- Statement 3: True
- Statement 4: False

The only true statement is **Statement 3**.

### Final Answer
The correct statement is **Statement 3**.

---