Which of the following will participate in intermolecular H-bonding?

Options

A. `CH_(2)Cl_(2)`
B. `H_(3)C-overset(O)overset(square)C-CH_(3)`
C. `H_(3)PO_(4)`
D. `PH_(3)`

Explanation

To determine which of the given compounds can participate in intermolecular hydrogen bonding, we need to analyze the structures of each compound and identify the presence of hydrogen atoms bonded to highly electronegative atoms (such as oxygen, nitrogen, or fluorine).

### Step-by-Step Solution:

1. **Understanding Hydrogen Bonding**:
- Hydrogen bonding occurs when hydrogen is covalently bonded to highly electronegative atoms like oxygen (O), nitrogen (N), or fluorine (F). The presence of these bonds allows hydrogen to interact with lone pairs of electrons on other electronegative atoms, forming a hydrogen bond.

2. **Analyzing CH2Cl2 (Dichloromethane)**:
- Structure: CH2Cl2 has a tetrahedral geometry with hydrogen atoms bonded to carbon (C).
- Conclusion: Since the hydrogen atoms are not bonded to electronegative atoms (O, N, or F), CH2Cl2 cannot participate in hydrogen bonding.

3. **Analyzing CH3COCH3 (Acetone)**:
- Structure: Acetone has a carbonyl group (C=O) with hydrogen atoms bonded to carbon.
- Conclusion: Although there is an oxygen atom in the structure, there are no hydrogen atoms directly bonded to oxygen. Therefore, acetone cannot form hydrogen bonds.

4. **Analyzing H3PO4 (Phosphoric Acid)**:
- Structure: H3PO4 has three hydrogen atoms bonded to oxygen atoms (O) and one phosphorus atom.
- Conclusion: The presence of hydrogen atoms bonded to oxygen means that H3PO4 can form hydrogen bonds with other molecules.

5. **Analyzing PH3 (Phosphine)**:
- Structure: PH3 has a pyramidal structure with hydrogen atoms bonded to phosphorus (P).
- Conclusion: Phosphorus is not highly electronegative like O, N, or F, and thus, PH3 cannot participate in hydrogen bonding.

### Final Conclusion:
Among the given compounds, only **H3PO4 (Phosphoric Acid)** can participate in intermolecular hydrogen bonding.