By X-ray studies, the packing atoms, in a crystal of gold is found to be in layers such that starting from any layer, every fourth layer is found to be exactly idenctical. The density of gold is found to be ` 19.4 g cm^(-3)` and its atomic mass is 197 a.m.u.
The coordination number of gold atom in the crystal is

Options

A. 4
B. 6
C. 8
D. 12

Explanation

To find the coordination number of gold atoms in the crystal, we can follow these steps:

### Step 1: Understand the Crystal Structure
The question states that the packing of atoms in the crystal of gold is such that every fourth layer is identical. This suggests a cubic close packing (CCP) arrangement, which is also known as face-centered cubic (FCC). In this arrangement, the atoms are packed closely together, maximizing the number of nearest neighbors.

**Hint:** Look for patterns in the arrangement of atoms to identify the type of packing.

### Step 2: Determine the Coordination Number
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