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 options is a sesquioxide, we need to understand what a sesquioxide is. A sesquioxide is an oxide that contains three atoms of oxygen for every two atoms of the other element. In the context of this question, we are looking for a nitrogen oxide.

### Step-by-Step Solution:

1. **Identify the Options**: The options provided are:
- N2O4
- N2O3
- N2O
- N2O5

2. **Understand the Definition of Sesquioxide**: A sesquioxide has the general formula of \(M_2O_3\), where \(M\) is the metal or non-metal. This means for every two atoms of the element, there are three atoms of oxygen.

3. **Analyze Each Option**:
- **Option 1: N2O4**: This has 4 oxygen atoms for 2 nitrogen atoms, which does not fit the sesquioxide formula.
- **Option 2: N2O3**: This has 3 oxygen atoms for 2 nitrogen atoms, which fits the sesquioxide formula \(M_2O_3\).
- **Option 3: N2O**: This has 1 oxygen atom for 2 nitrogen atoms, which does not fit the sesquioxide formula.
- **Option 4: N2O5**: This has 5 oxygen atoms for 2 nitrogen atoms, which does not fit the sesquioxide formula.

4. **Conclusion**: The only option that fits the definition of a sesquioxide is **N2O3**.

### Final Answer:
The sesquioxide among the given options is **N2O3**.