Which of the following possess `2 : 1` type of structure.

Options

A. `CaO`
B. `Li_(2)O`
C. `CaF_(2)`
D. `CsBr`

Answer

To determine which of the given compounds possesses a `2:1` type of structure, we need to analyze the ratio of cations to anions in each compound. The `2:1` structure indicates that for every two cations, there is one anion.

### Step-by-Step Solution:

1. **Understand the `2:1` Structure**:
- The `2:1` structure means that there are two cations for every one anion in the compound. This is a common structure in certain ionic compounds.

2. **Identify the Compounds**:
- We need to look at the options provided (though not explicitly listed here) and identify the ionic compounds that could potentially have a `2:1` ratio.

3. **Analyze Lithium Oxide (Li₂O)**:
- In lithium oxide, there are two lithium ions (Li⁺) for every one oxide ion (O²⁻).
- Therefore, the formula for lithium oxide is Li₂O, which confirms the `2:1` ratio of cations to anions.

4. **Conclusion**:
- Based on the analysis, lithium oxide (Li₂O) is the compound that possesses a `2:1` type of structure.

### Final Answer:
The compound that possesses a `2:1` type of structure is **Li₂O (Lithium Oxide)**.

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