Question

What is the distinguishing layer between hexagonal close packing and cubic close packing?

• A. First layer
• B. Second layer
• C. Third layer
• D. All layers

Answer 1

The correct option is C

Third layer

If the third layer is identical to the first layer (A), it is called hexagonal close packing (hcp) & arrangement will be AB-AB-AB. If a different third layer (C) is formed above the layers A and B, its called cubic close packing (ccp) & arrangement will be ABC-ABC-ABC.