An `AB_(2)` type structure is found in:

Options

A. NaCl
B. `AI_(2)O_(3)`
C. `CaF_(2)`
D. `N_(2)O`

Answer

To determine the compound that exhibits an AB₂ type structure, we can follow these steps:

### Step 1: Understand the AB₂ Structure
The AB₂ structure indicates that for every one cation (A), there are two anions (B). In this structure, the cation is typically larger than the anion.

**Hint:** Remember that in AB₂ structures, the ratio of cations to anions is crucial.

### Step 2: Identify Examples of AB₂ Structures
Common examples of compounds with an AB₂ structure include calcium fluoride (CaF₂) and strontium fluoride (SrF₂). In these compounds, the cation (Ca²⁺ or Sr²⁺) is larger than the anion (F⁻).

**Hint:** Look for compounds where the cation is a divalent metal and the anion is a monovalent non-metal.

### Step 3: Analyze the Ionic Radii
In the AB₂ structure, the ionic radii ratio of the anion to the cation is significant. For CaF₂, the ionic radius of Ca²⁺ is larger than that of F⁻. The ratio of the radii (r⁻/r²⁺) falls between 0.225 and 0.414, which is characteristic of an AB₂ type structure.

**Hint:** Check the ionic radii values in a table to confirm the size relationship between cations and anions.

### Step 4: Confirm the Structure
In the case of CaF₂, the structure can be described as follows:
- The Ca²⁺ ions form a face-centered cubic (FCC) lattice.
- The F⁻ ions occupy the tetrahedral voids within the lattice.

This arrangement confirms the AB₂ type structure.

**Hint:** Visualizing the crystal structure can help in understanding how the ions are arranged.

### Step 5: Conclusion
Based on the analysis, the compound that exhibits an AB₂ type structure is calcium fluoride (CaF₂).

**Final Answer:** The AB₂ type structure is found in CaF₂ (Calcium Fluoride).