The most stable oxides of nitrogen will be :

Options

A. (a) `2NO_(2)(g)hArrN_(2)(g)+2O_(2)(g), ,K=6.7xx10^(16)molL^(-1)`
B. (b) `2N_(2)O_(5)(g)hArr2N_(2)(g)+50_(2)(g),,K=1.2xx10^(-24)mol^(5)L^(-5)`
C. (c) `2NO(g)hArrN_(2)(g)+O_(2)(g), ,K=2.2xx10^(30)`
D. (d) `2N_(2)O(g)hArr2N_(2)(g)+O_(2)(g), , K=3.5xx10^(33),molL^(-1)`

Answer

To determine the most stable oxides of nitrogen from the given options (NO2, N2O5, NO, and N2O), we will analyze the equilibrium constants provided for their respective reactions.

### Step-by-Step Solution:

1. **Understanding the Equilibrium Constant (K)**:
The equilibrium constant (K) indicates the extent of a reaction at equilibrium. A higher K value suggests that the products are favored, while a lower K value indicates that the reactants are favored.

2. **Given Equilibrium Constants**:
- For NO2: K = 6.7 × 10^16
- For N2O5: K = 1.2 × 10^-24
- For NO: K = 2.2 × 10^30
- For N2O: K = 3.5 × 10^33

3. **Analyzing the Values**:
To find the most stable oxide, we need to look for the oxide with the lowest equilibrium constant because stability is inversely proportional to the equilibrium constant.

4. **Comparing the K Values**:
- NO2 has K = 6.7 × 10^16 (high)
- N2O5 has K = 1.2 × 10^-24 (very low)
- NO has K = 2.2 × 10^30 (very high)
- N2O has K = 3.5 × 10^33 (very high)

5. **Identifying the Most Stable Oxide**:
Among the given oxides, N2O5 has the lowest equilibrium constant (K = 1.2 × 10^-24). Therefore, it is the most stable oxide of nitrogen.

### Conclusion:
The most stable oxide of nitrogen is **N2O5**.

---