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In a face-centered cubic (fcc) lattice, the face diagonal equals four times the atomic radius. If the face diagonal of a copper crystal is given as 512 pm, what is the atomic radius?

1. 512 pm
2. 362 pm
3. 128 pm
4. 10⁻¹² cm

Correct answer: 128 pm

Solution

The atomic radius can be calculated by dividing the face diagonal by four, which results in 128 pm for the given face diagonal of 512 pm.

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