Copper metal is known to crystallize in a face-centered cubic (fcc) unit cell. What is the coordination number of a copper atom?

Question

Copper metal is known to crystallize in a face-centered cubic (fcc) unit cell.  What is the coordination number of a copper atom?

BlackTom AI · Accepted Answer

Let's parse the question carefully: copper crystallizes in a face-centered cubic (fcc) unit cell, and we are asked for the coordination number (CN) of a copper atom in that structure.
Option 1: 'None of the others.' This is a catch-all incorrect choice unless none of the listed options were plausible; since fcc coordination is a well-known value, this is not a valid generic answer.
Option 2: '8' In a simple cubic array, each atom touches 6 neighbors, giving CN = 6. In a body-centered or simple cubic context you might see 8 in other lattice considerations, but not for fcc copper. Here 8 would misrepresent the actual neighbor count in fcc.
Option 3: 'It depends whether you are talking about a copper atom on a corner, or a copper atom on a face!' In an fcc lattice, all lattice sites are equivalent by symmetry; a corner atom and a face-centered atom share the same coordination number due to the periodic arrangement, so this conditional statement is incorrect for a pure fcc crystal.
Option 4: '6' A coordination number of 6 corresponds to a simple cubic or a hexagonal close-packed environment, not fcc. In fcc, each atom has more neighbors than in simple cubic, so 6 is too low for copper in fcc.
Option 5: '12' In an fcc structure, each atom is in contact with 12 nearest neighbors: 4 in the same layer (via the face-centered positions), 4 in the layer above, and 4 in the layer below when considering the packing arrangement. This results from the close-packed nature of fcc, where spheres touch along the 12 close-packed directions, giving CN = 12.
Putting these together, the statement in Option 5 aligns with the known geometry of fcc crystals, whereas the other options rely on incorrect counts or misunderstandings of equivalence of lattice sites.

Copper metal is known to crystallize in a face-centered cubic (fcc) unit cell. What is the coordination number of a copper atom?

View Explanation

Log in for full answers

Similar Questions

What does it mean to be crystalline? Choose the best answer.

The smallest group of particles in a crystal that retains the shape of the crystal is called the ____.

Which one oft he following has a structure, which is very different to the other three?

An ionic solid composed of Ba, Zr, and O ions has the cubic unit cell shown above. The unit cell has barium atoms at the corners, a zirconium atom in the cube center, and oxygen anions in the cube faces. What is the empirical formula of the compound?

A metallic element crystallizes in the unit cell shown in the diagram. Which of the following apply to this unit cell?

Rhodium (Rh) crystallizes in a face-centered cubic unit cell. The radius of a rhodium atom is 135 pm. Determine the density of rhodium in g·cm–3.

Which of the following statements about metallic copper (Cu) which crystallizes in a face-centered cubic unit cell arrangement is NOT correct?

More Practical Tools for Students Powered by AI Study Helper

Homework AI Solver

Stylized AI Paper Writer

Plagiarism Checker Assistant

Citation AI Academic Writing Tool

In-Class Translation Assistant

AI Note Generator

AI Quiz Answers

Past Exam Questions from University Test Bank

Smart Practice Assistant

Adaptive Practice

Making Your Study Simpler