What is the coordination number of copper in its crystalline state ?

Explanation

To determine the coordination number of copper in its crystalline state, we follow these steps:

### Step 1: Understand the Structure of Copper
Copper crystallizes in a face-centered cubic (FCC) lattice structure. In this structure, atoms are located at each corner of the cube and at the centers of each face.

### Step 2: Visualize the FCC Structure
Draw a cube to represent the FCC lattice. Place copper atoms at the corners of the cube and at the center of each face.

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