Which of the following compounds contain(s) no covalent bond(s)?
` KCl, ,PH_3 ,O_2 ,B_2 H_6 ,H_2 SO_4`

Options

A. `KCl, B_2 H_6, PH_3`
B. `KCl,H_2SO_4`
C. `KCl`
D. `KCl,B_2H_6`

Explanation

To determine which of the given compounds contains no covalent bonds, we will analyze each compound one by one.

1. **KCl (Potassium Chloride)**:
- KCl is formed by the transfer of an electron from potassium (K) to chlorine (Cl), resulting in the formation of K⁺ and Cl⁻ ions. This transfer of electrons leads to the formation of ionic bonds. Therefore, KCl does not contain any covalent bonds.

2. **PH₃ (Phosphine)**:
- PH₃ consists of phosphorus (P) bonded to three hydrogen (H) atoms. The bonds formed between phosphorus and hydrogen are covalent bonds. Thus, PH₃ contains covalent bonds.

3. **O₂ (Oxygen)**:
- O₂ is a diatomic molecule where two oxygen atoms are bonded together by a double covalent bond. Therefore, O₂ contains covalent bonds.

4. **B₂H₆ (Diborane)**:
- B₂H₆ is a compound that consists of two boron (B) atoms and six hydrogen (H) atoms. The bonds between boron and hydrogen are covalent, including unique "banana bonds." Hence, B₂H₆ contains covalent bonds.

5. **H₂SO₄ (Sulfuric Acid)**:
- H₂SO₄ consists of sulfur (S) bonded to four oxygen (O) atoms and two hydrogen (H) atoms. The bonds between sulfur and oxygen, as well as between sulfur and hydrogen, are covalent bonds. Therefore, H₂SO₄ contains covalent bonds.

**Conclusion**:
Among the compounds listed, only KCl contains no covalent bonds. The remaining compounds (PH₃, O₂, B₂H₆, and H₂SO₄) all contain covalent bonds.

**Final Answer**: KCl is the compound that contains no covalent bonds.

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