Question

The packing fraction of a crystal structure is 74%. The crystal structure is

• A. Simple cubic structure
• B. Face-centred cubic structure
• C. Body-centred cubic structure
• D. Crystal structure of Tungsten

Hint:

Packing efficiency: SC (52%), BCC (68%), FCC/CCP (74%), HCP (74%).

Answer 1

The Correct Option is B

Step 1: Packing Fractions.
- Simple cubic (SC): 52.4%.
- Body-centered cubic (BCC): 68.0%.
- Face-centered cubic (FCC): 74.0%.
Step 2: Structure Identification.
The 74% packing fraction corresponds to the FCC structure (also known as cubic close packing, CCP).
Final Answer: \[ \boxed{\text{Face-centred cubic structure}} \]