Which one is a polar covalent compound?
KCl ; NaCl ; C C l 4 ; HCl ;

Options

A. KCl
B. NaCl
C. `C Cl_4`
D. HCl

Explanation

To determine which of the given compounds is a polar covalent compound, we will analyze each option based on their bonding characteristics and electronegativity differences.

### Step-by-Step Solution:

1. **Identify the Compounds**: The compounds given are KCl, NaCl, CCl4, and HCl.

2. **Analyze KCl**:
- KCl (Potassium Chloride) is formed between a metal (K) and a non-metal (Cl).
- Potassium (K) is electropositive and Chlorine (Cl) is highly electronegative.
- The difference in electronegativity is significant, leading to the formation of ionic bonds.
- **Conclusion**: KCl is an ionic compound.

3. **Analyze NaCl**:
- NaCl (Sodium Chloride) is also formed between a metal (Na) and a non-metal (Cl).
- Sodium (Na) is electropositive and Chlorine (Cl) is highly electronegative.
- Similar to KCl, the difference in electronegativity results in ionic bonding.
- **Conclusion**: NaCl is an ionic compound.

4. **Analyze CCl4**:
- CCl4 (Carbon Tetrachloride) consists of one carbon atom and four chlorine atoms.
- The bonds between carbon and chlorine are covalent. However, since the molecule is symmetrical (tetrahedral), the dipoles cancel each other out.
- **Conclusion**: CCl4 is a non-polar covalent compound.

5. **Analyze HCl**:
- HCl (Hydrochloric Acid) is formed between hydrogen (H) and chlorine (Cl).
- The electronegativity of chlorine is significantly higher than that of hydrogen, resulting in a polar covalent bond.
- The molecule has a permanent dipole due to the unequal sharing of electrons.
- **Conclusion**: HCl is a polar covalent compound.

### Final Answer:
The polar covalent compound among the given options is **HCl**.

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