Chem 1E-Crystals

It has regular and repeating arrangement of components in a solid. Have a sharp melting point. Definite heat fusion. Example is diamond.

• crystalline solid
• amorphous solid
• liquid
• gas

It is the basic structural unit of a crystalline solid.

• molecule
• unit cell

• element
• cell

What type of unit cell is this?

• Cubic
• Tetragonal
• Triclinic

• Hexagonal

One of the important characteristic of a crystal structure in which it is the number of nearest-neighbor or touching atoms

• lattice structure
• atomic radius
• coordination number
• crystal lattice

Define atomic packing factor

• The atomic packing factor is the ratio of the number of atoms in a unit cell to the total number of atoms in the crystal.
• The atomic packing factor is the ratio of the volume occupied by atoms in a unit cell to the volume of the crystal lattice.
• The atomic packing factor is the ratio of the total volume of the unit cell to the volume occupied by atoms in the unit cell.
• The atomic packing factor is the ratio of the volume occupied by atoms in a unit cell to the total volume of the unit cell.

What crystal structure is this?

• HCP

• FCC

• BCC

• SC

What is the atomic packing factor of Face-centered cubic structure?

• 0.5
• 1.0
• 0.68

• 0.74

What cubic structure has this relationship between the edge length and the atomic radius?

• Face-Centered Cubic (FCC)
• Simple Cubic (SC)
• Hexagonal Close-Packed (HCP)
• Body-Centered Cubic (BCC)

How many atoms are assigned to each unit cell of a hexagonal closed-packed crystal structure?

• 4
• 12
• 8
• 6

It gives the most accurate method for determining bond lengths and bond angles in molecules in the solid state.

• Nuclear magnetic resonance
• Mass spectrometry
• X-ray crystallography
• Infrared spectroscopy