The oxide which is most acidic is :

Options

A. `Bi_2O_3`
B. `As_2O_(3)`
C. `P_2O_3`
D. `N_2O_3`

Answer

To determine which oxide is the most acidic among the given options (Bi2O3, H2O3, P2O3, N2O3), we can follow these steps:

### Step 1: Identify the Elements and Their Oxides
The elements involved in the oxides are:
- Bismuth (Bi) in Bi2O3
- Hydrogen and Oxygen in H2O3 (which is also known as trioxide)
- Phosphorus (P) in P2O3
- Nitrogen (N) in N2O3

### Step 2: Understand the Group Trends
These elements belong to Group 15 of the periodic table:
- Nitrogen (N)
- Phosphorus (P)
- Arsenic (As)
- Antimony (Sb)
- Bismuth (Bi)

As we move down the group from nitrogen to bismuth, the nature of their oxides changes from acidic to basic.

### Step 3: Analyze the Acidity of Each Oxide
- **N2O3**: This oxide is acidic. It can react with water to form nitric acid (HNO3).
- **P2O3**: This oxide is also acidic, but less so than N2O3. It can form phosphorous acid (H3PO3) when reacted with water.
- **H2O3**: This is a less common oxide and is generally considered to be weakly acidic.
- **Bi2O3**: This oxide is basic in nature and does not exhibit significant acidity.

### Step 4: Compare the Acidity
From the analysis:
- N2O3 is the most acidic.
- P2O3 is less acidic than N2O3.
- H2O3 is weakly acidic.
- Bi2O3 is basic.

### Conclusion
Thus, the oxide which is most acidic among the given options is **N2O3**.

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