When addition of `Br_2` was carried out in presence of aq. NaCl on ethene than total number of possible products is:

Explanation

To solve the problem of determining the total number of possible products when bromine (Br₂) is added to ethene (C₂H₄) in the presence of aqueous NaCl, we can follow these steps:

### Step 1: Understand the Reactants
- Ethene (C₂H₄) is an alkene with a double bond between the two carbon atoms.
- Bromine (Br₂) is a diatomic molecule that can undergo electrophilic addition.
- Aqueous NaCl provides sodium ions (Na⁺) and chloride ions (Cl⁻), as well as water (H₂O) which can act as a nucleophile.

### Step 2: Identify the Mechanism
- The addition of Br₂ to ethene occurs via an electrophilic addition mechanism. The double bond in ethene acts as a nucleophile and attacks one of the bromine atoms, resulting in the formation of a bromonium ion intermediate.

### Step 3: Formation of the Bromonium Ion
- When Br₂ approaches ethene, the double bond attacks one bromine atom, leading to the formation of a bromonium ion (C₂H₄Br⁺). This intermediate has a positive charge on one of the carbon atoms.

### Step 4: Nucleophilic Attack
- The bromonium ion can be attacked by different nucleophiles present in the solution:
- **Bromide ion (Br⁻)**: This can attack the bromonium ion to form 1,2-dibromoethane (C₂H₄Br₂).
- **Chloride ion (Cl⁻)**: This can also attack the bromonium ion to form 1-bromo-2-chloroethane (C₂H₄BrCl).
- **Water (H₂O)**: Water can also attack the bromonium ion, leading to the formation of 1-bromo-2-hydroxyethane (C₂H₄BrOH).

### Step 5: Count the Products
- From the above nucleophilic attacks, we can summarize the possible products:
1. 1,2-dibromoethane (C₂H₄Br₂)
2. 1-bromo-2-chloroethane (C₂H₄BrCl)
3. 1-bromo-2-hydroxyethane (C₂H₄BrOH)

### Conclusion
- Therefore, the total number of possible products formed when Br₂ is added to ethene in the presence of aqueous NaCl is **3**.

### Final Answer:
The total number of possible products is **3**.

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