Face Centered Cubic (FCC) Structures

The video tutorial explains the face-centered cubic (FCC) structure, highlighting its unique arrangement where atoms are positioned at the center of each face of the cube. It contrasts FCC with body-centered cubic structures, emphasizing how atoms touch along face diagonals. The tutorial also covers the coordination number, which is 12 for FCC, and details the calculation of the atomic packing factor, which is 0.74, indicating that 74% of the cube's volume is occupied by atoms. Examples of elements with FCC structures, such as aluminum and gold, are provided.

What is the defining feature of a Face Centered Cubic (FCC) structure?

• Atoms are located at the corners and the center of each face.

• Atoms are located only at the center of the cube.

• Atoms are located at the corners and the center of the cube.

• Atoms are located only at the corners.

Which of the following metals is an example of an FCC structure?

• Iron

• Bismuth

• Aluminum

• Tungsten

Which of the following statements is true about the FCC structure?

• Atoms are only at the corners.

• Atoms are only at the face centers.

• Atoms are at the corners and body center.

• Atoms are at the corners and face centers.

In an FCC structure, how do atoms touch each other?

• Along the body diagonals.

• Along the face diagonals.

• Along the edges of the cube.

• They do not touch each other.

What is the coordination number of an atom in an FCC structure?

• 10

• 6

• 12

• 8

How does the coordination number in FCC compare to that in BCC?

• BCC has a higher coordination number.

• Coordination number is not defined for BCC.

• FCC has a higher coordination number.

• Both have the same coordination number.

How many atoms are there in a unit cell of an FCC structure?

• 1

• 2

• 3

• 4

What is the atomic packing factor (APF) for an FCC structure?

• 0.82

• 0.74

• 0.68

• 0.52

In an FCC structure, what is the relationship between the edge length 'a' and the atomic radius 'r'?

• a = 4√2r

• a = 2√2r

• a = 4r

• a = 2r

What percentage of the total volume is occupied by atoms in an FCC structure?

• 74%

• 82%

• 68%

• 52%