Which of these has a layered arrangement?

Options

A. `Cdl_(2)`
B. Mg
C. KCl
D. `NH_(4)Br`

Answer

To determine which of the given substances has a layered arrangement, we can analyze the structures of the compounds mentioned.

### Step-by-Step Solution:

1. **Understanding Layered Arrangements**:
- Layered arrangements in solids typically refer to structures where atoms or molecules are organized in distinct layers. Common examples include certain ionic compounds and layered materials like graphite.

2. **Identifying Common Structures**:
- Two common types of close packing arrangements are:
- **Hexagonal Close Packing (HCP)**: Atoms are arranged in a hexagonal pattern, with layers stacked in an ABAB... sequence.
- **Cubic Close Packing (CCP)**: Atoms are arranged in a cubic pattern, with layers stacked in an ABCABC... sequence.

3. **Analyzing the Given Compounds**:
- The question implies that we need to identify a compound that exhibits a layered structure. One example provided in the transcript is **CdCl2 (Cadmium Chloride)**.

4. **Structure of CdCl2**:
- Cadmium chloride has a layered structure where cadmium ions and chloride ions are arranged in alternating layers. This layered arrangement is characteristic of many ionic compounds, allowing for easy cleavage along the layers.

5. **Conclusion**:
- Based on the analysis, **CdCl2** is an example of a compound that has a layered arrangement.

### Final Answer:
**CdCl2 (Cadmium Chloride) has a layered arrangement.**

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