Chapter 1: Structure of Materials - Topic 1 (1.1-1.3) Vocabulary

Vocabulary flashcards covering atom arrangement, basic atom structure, and atomic bonding as described in the lecture notes.

Molecular

An arrangement where atoms form discrete molecules; molecules are held together by covalent bonds (examples: H2O, O2).

Crystal

A regular, three-dimensional lattice of atoms with a repeating unit cell (examples: metals, snowflakes, diamonds).

Amorphous

Lack of long-range order; atoms/molecules are not arranged in a definite lattice (examples: ceramic, glass, plastic, gel).

Atom

The basic unit of an element consisting of a nucleus and surrounding electrons; essential unit of chemical structure.

Neutron

Neutral subatomic particle in the nucleus of an atom.

Proton

Positively charged subatomic particle in the nucleus; determines atomic number.

Electron

Negatively charged subatomic particle orbiting the nucleus; involved in bonding.

Bohr model

Atomic model describing electrons in defined orbits around the nucleus; foundational for basic atomic structure.

Unit Cell

The smallest repeating unit of a crystal lattice that builds the overall crystal structure.

Lattice

A regular, three-dimensional arrangement of atoms in a crystal space.

Ionic Bond

Bond formed by transfer of electrons creating oppositely charged ions; strong electrostatic attraction between cation and anion (metal to non-metal).

Covalent Bond

Bond formed by sharing valence electrons between atoms; strong bond typically between non-metals.

Metallic Bond

Bond due to attraction between metal cations and a sea of delocalized electrons; occurs between metals.

Van der Waals / Hydrogen Bond

Weak intermolecular attractions; hydrogen bonds are a type of Van der Waals interaction; important in molecules like water, DNA.

Delocalized electrons

Electrons in a metal lattice that are not bound to a single atom and can move freely, enabling metallic bonding.

Structure-property relationship

Concept that a material's microscopic structure and bonding determine its macroscopic properties (strength, conductivity, etc.).