Which of the following is a sesqui oxide ?

Options

A. `N_2 O_4`
B. `N_2 O_3`
C. `N_2 O`
D. `N_2 O_5`

Answer

To determine which of the given compounds is a sesquioxide, we first need to understand the definition of a sesquioxide. A sesquioxide is an oxide that contains three atoms of oxygen for every two atoms of another element. This can be expressed as a ratio of 3:2 (O:Element).

### Step-by-Step Solution:

1. **Identify the Definition of Sesquioxide:**
- A sesquioxide is defined as an oxide that contains three atoms of oxygen (O) for every two atoms of another element (E).
- This can be represented by the formula \( E_2O_3 \).

2. **Analyze the Given Options:**
- We will evaluate each option to see if it fits the 3:2 ratio of oxygen to the other element.

3. **Option Analysis:**
- **Option 1: \( N_2O_4 \)**
- Oxygen: 4 atoms
- Other element (Nitrogen): 2 atoms
- Ratio: \( \frac{4}{2} = 2:1 \) (Not a sesquioxide)

- **Option 2: \( N_2O_3 \)**
- Oxygen: 3 atoms
- Other element (Nitrogen): 2 atoms
- Ratio: \( \frac{3}{2} = 3:2 \) (This is a sesquioxide)

- **Option 3: \( N_2O \)**
- Oxygen: 1 atom
- Other element (Nitrogen): 2 atoms
- Ratio: \( \frac{1}{2} = 1:2 \) (Not a sesquioxide)

- **Option 4: \( N_2O_5 \)**
- Oxygen: 5 atoms
- Other element (Nitrogen): 2 atoms
- Ratio: \( \frac{5}{2} = 2.5:1 \) (Not a sesquioxide)

4. **Conclusion:**
- The only option that matches the definition of a sesquioxide (3:2 ratio) is **Option 2: \( N_2O_3 \)**.

### Final Answer:
**Option 2: \( N_2O_3 \) is a sesquioxide.**

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