Phosphoric acid is syrupy in nature due to hydrogen bonding. Each molecule of `H_3 PO_4` is surrounded by

Options

A. `4-H-bonds`
B. `5-H-bonds`
C. `2-H-bonds`
D. Infinite-H-bonds

Answer

To solve the question regarding how many hydrogen bonds each molecule of phosphoric acid (H₃PO₄) is surrounded by, we can follow these steps:

### Step 1: Understand the Structure of Phosphoric Acid
Phosphoric acid (H₃PO₄) consists of one phosphorus atom bonded to four oxygen atoms. Three of these oxygen atoms are bonded to hydrogen atoms (–OH groups), while one oxygen is involved in a double bond with phosphorus.

### Step 2: Identify the Hydrogen Bonds
A hydrogen bond is formed between a hydrogen atom that is covalently bonded to an electronegative atom (like oxygen) and another electronegative atom. In H₃PO₄, the –OH groups are capable of forming hydrogen bonds with the oxygen atoms of other H₃PO₄ molecules.

### Step 3: Count the Hydrogen Bonds
Each H₃PO₄ molecule can form hydrogen bonds as follows:
- Each of the three hydrogen atoms from the –OH groups can form a hydrogen bond with the oxygen atom of another H₃PO₄ molecule.
- Therefore, each H₃PO₄ molecule can form a total of 3 hydrogen bonds with other molecules.

### Step 4: Consider the Interaction with Other Molecules
In addition to the hydrogen bonds formed by the three –OH groups, the double-bonded oxygen can also interact with hydrogen atoms from other H₃PO₄ molecules. However, in the context of the question, we focus on the primary hydrogen bonds formed by the –OH groups.

### Conclusion
After analyzing the structure and the bonding capabilities of H₃PO₄, we conclude that each molecule of phosphoric acid is surrounded by **4 hydrogen bonds** (3 from the –OH groups and 1 from the double-bonded oxygen interacting with another molecule).

### Final Answer
Each molecule of H₃PO₄ is surrounded by **4 hydrogen bonds**.

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