Which of the following is most acidic ?

Options

A. `N_(2)O_(5)`
B. `P_(2)O_(5)`
C. `As_(2)O_(5)`
D. `Sb_(2)O_(5)`

Explanation

To determine which of the following oxides is the most acidic among the group 15 elements (N, P, As, Sb), we can follow these steps:

### Step 1: Identify the Group 15 Elements
The elements in group 15 of the periodic table are Nitrogen (N), Phosphorus (P), Arsenic (As), and Antimony (Sb). Each of these elements can form oxides.

### Step 2: List the Common Oxides
The common oxides of these elements are:
- Nitrogen: N2O5, NO, NO2, N2O3
- Phosphorus: P2O5, P4O10
- Arsenic: As2O5
- Antimony: Sb2O5

### Step 3: Understand Acidic and Basic Character
In general, as we move down a group in the periodic table:
- The acidic character of oxides decreases.
- The basic character of oxides increases.

This trend is due to the decrease in electronegativity as we move down the group. More electronegative elements tend to form more acidic oxides.

### Step 4: Compare Electronegativity
Among the group 15 elements:
- Nitrogen is the most electronegative.
- Phosphorus is less electronegative than nitrogen.
- Arsenic is less electronegative than phosphorus.
- Antimony is the least electronegative.

### Step 5: Determine the Most Acidic Oxide
Since nitrogen is the most electronegative element in group 15, its oxides will exhibit the highest acidic character. The oxide N2O5 is known to be a strong acid (it forms nitric acid when dissolved in water).

### Conclusion
Thus, the most acidic oxide among the given options is **N2O5**.

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