Lecture on Density, Stiffness, and Atomic Packing

Flashcards covering key concepts related to density, stiffness, atomic packing, and materials science.

Density

Mass per unit volume of a material, affected by atomic weight, size, and packing.

Stiffness

The rigidity of an object; the extent to which it resists deformation.

Elastic Modulus

A measure of a material's ability to deform elastically (i.e., non-permanently) when a force is applied.

Atomic Packing Factor (APF)

The fraction of volume in a crystal structure that is occupied by the atoms.

Unit Cell

The smallest repeating unit of a crystal lattice that shows the complete structure of the crystal.

Crystalline Material

Materials that have a regularly repeating pattern of structural units.

Amorphous Material

Materials that do not have a long-range order or crystalline structure.

Face-Centered Cubic (FCC)

A type of crystal structure where atoms are located at each of the corners and the centers of all the cube faces.

Body-Centered Cubic (BCC)

A crystal structure where one atom is at the center of the cube and one atom at each corner.

Thermoplastics

Polymeric materials that become pliable or moldable above a specific temperature and solidify upon cooling.

Thermosets

Polymeric materials that are set into a given shape when cured and cannot be remolded.

Quenching

A rapid cooling process used to produce amorphous structured materials.

Packing Fraction

The ratio of the volume occupied by particles to the total volume of the container that holds them.

Polyethylene

A common thermoplastic polymer used in a variety of applications.

Polyvinyl Chloride (PVC)

A widely used synthetic plastic polymer that is commonly used in plumbing, wiring, and credit cards.

Polytetrafluoroethylene (PTFE)

A type of fluoropolymer best known by the brand name Teflon, which is non-stick and heat-resistant.