Which of the following is a sesquioxide ?

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 following compounds is a sesquioxide, we need to understand what a sesquioxide is. A sesquioxide is an oxide containing three atoms of oxygen for every two atoms of another element. In the case of nitrogen oxides, we are looking for the one that fits this definition.

### Step-by-Step Solution:

1. **Identify the Compounds**: The question provides four nitrogen oxides:
- N2O4 (Dinitrogen Tetroxide)
- N2O3 (Dinitrogen Trioxide)
- N2O (Dinitrogen Oxide)
- N2O5 (Dinitrogen Pentoxide)

2. **Define Sesquioxide**: A sesquioxide has the general formula of \( A_2O_3 \), where A is a metal or non-metal. This means that for every two atoms of the element, there are three atoms of oxygen.

3. **Analyze Each Compound**:
- **N2O4**: This is dinitrogen tetroxide, which has the formula \( N_2O_4 \) (not a sesquioxide).
- **N2O3**: This is dinitrogen trioxide, which has the formula \( N_2O_3 \). It fits the sesquioxide definition because it can be viewed as having 2 nitrogen atoms and 3 oxygen atoms.
- **N2O**: This is dinitrogen oxide, which has the formula \( N_2O \) (not a sesquioxide).
- **N2O5**: This is dinitrogen pentoxide, which has the formula \( N_2O_5 \) (not a sesquioxide).

4. **Conclusion**: Among the options provided, the only compound that fits the definition of a sesquioxide is **N2O3** (Dinitrogen Trioxide).

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