Crystal Structures and Unit Cells

The video explores crystal structures, focusing on unit cells in cubic systems. It details simple, body-centered, and face-centered cubic unit cells, explaining their coordination numbers and particle arrangements. The video also discusses stacking methods and their efficiency, highlighting the structures of ionic compounds like sodium chloride and zinc sulfide.

What is the smallest portion of a crystal structure that defines its overall structure?

• Atom

• Unit cell

• Ion

• Molecule

In a simple cubic unit cell, how many nearest neighbors does each particle have?

• Four

• Six

• Twelve

• Eight

Which of the following is true about the simple cubic unit cell?

• Particles touch along the cube edges and diagonals

• Particles only touch along the cube edges

• Particles touch along the face diagonals

• Particles do not touch at all

How many particles are there in a body-centered cubic unit cell?

• Three

• Two

• Four

• One

In a body-centered cubic unit cell, how many nearest neighbors does each particle have?

• Eight

• Twelve

• Six

• Ten

How many particles are there in a face-centered cubic unit cell?

• Two

• Five

• Three

• Four

In a face-centered cubic unit cell, how many nearest neighbors does each particle have?

• Twelve

• Ten

• Eight

• Six

What percentage of volume is occupied by spheres in a simple cubic unit cell?

• 74%

• 52%

• 68%

• 80%

Which stacking arrangement is based on the face-centered cubic unit cell?

• Hexagonal closest packing

• Cubic closest packing

• Body-centered cubic packing

• Simple cubic packing

Which structure is adopted by sodium chloride in its crystalline form?

• Zinc blend structure

• Rock salt structure

• Diamond structure

• Hexagonal structure