`BCl_(3)` is an electron-deficient compound.

Answer

To determine whether BCl₃ (Boron Trichloride) is an electron-deficient compound, we can analyze its structure and the electron configuration of boron.

### Step-by-Step Solution:

1. **Identify the Central Atom**:
- In BCl₃, the central atom is boron (B).

2. **Determine the Atomic Number and Electron Configuration of Boron**:
- Boron has an atomic number of 5.
- Its electron configuration is 1s² 2s² 2p¹.

3. **Count the Valence Electrons**:
- Boron has 3 valence electrons (2 from 2s and 1 from 2p).

4. **Analyze the Bonding in BCl₃**:
- Boron forms three covalent bonds with three chlorine (Cl) atoms.
- Each chlorine atom contributes one electron to the bond.

5. **Calculate the Total Electrons Around Boron**:
- After forming three bonds with chlorine, boron effectively shares three additional electrons.
- Therefore, boron has a total of 6 electrons around it (3 from its own valence electrons and 3 shared with chlorine).

6. **Determine if Boron Completes its Octet**:
- An octet consists of 8 electrons.
- Since boron only has 6 electrons around it, it is lacking 2 electrons to complete its octet.

7. **Conclusion**:
- Since boron in BCl₃ does not have a complete octet and has fewer than 8 electrons, it is classified as an electron-deficient compound.

### Final Statement:
Thus, the statement that BCl₃ is an electron-deficient compound is **true**.

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