A Sample of Co Crystallizes in the Hexagonal Closest-Packed (Hcp)

question 37

Multiple Choice

A sample of Co crystallizes in the hexagonal closest-packed (hcp) structure. Each atom in a layer is surrounded by and touches 6 other Co atoms. If the distance between Co atom centers within each layer is 2.0 × 10² pm, what is the distance between centers of nearest neighbors in adjacent layers?

• A) 1.5 × 10² pm
• B) 4.0 × 10² pm
• C) 2.3 × 10² pm
• D) 2.0 × 10² pm
• E) none of these

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