Charge on cation in product formed when `BeCl_2` reacts with concentrated diethyl ether solution.

Explanation

To determine the charge on the cation formed when BeCl₂ reacts with concentrated diethyl ether solution, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: The reactants are beryllium chloride (BeCl₂) and concentrated diethyl ether (C₂H₅)₂O.

2. **Understand the Reaction**: When BeCl₂ reacts with diethyl ether, it forms a complex. The beryllium ion (Be²⁺) interacts with the ether molecules.

3. **Determine the Stoichiometry**: In this reaction, 3 molecules of BeCl₂ react with 6 molecules of diethyl ether. This stoichiometry indicates that each beryllium atom will coordinate with two ether molecules.

4. **Formation of the Cation**: The product formed is a complex where beryllium is coordinated with ether. The structure can be represented as:
- BeCl₂ + 3(C₂H₅)₂O → [Be(C₂H₅)₂O]₃ + 3Cl⁻

5. **Charge Analysis**: In the product, the beryllium ion (Be) has a +2 oxidation state. However, since it is coordinated with ether, it can effectively exhibit a +3 charge due to the formation of a cationic complex.

6. **Conclusion**: The charge on the cation in the product formed is +3.

### Final Answer:
The charge on the cation in the product formed when BeCl₂ reacts with concentrated diethyl ether is +3.

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