Aero 413: Aerospace Materials Science - Atomic Structure and Interatomic Bonding

A collection of vocabulary flashcards summarizing key terms and definitions from the lecture notes on atomic structure and interatomic bonding.

Atomic number

Number of protons in the nucleus of an atom.

Atomic weight

Weight of 6.022 × 10^23 atoms, also known as Avogadro’s number.

Atomic mass unit (amu)

1/12 of the mass of carbon-12.

Valence electrons

Electrons in the outer unfilled shells, responsible for bonding.

Covalent bond

A bond involving the sharing of electrons between two atoms.

Ionic bond

A bond that involves the transfer of electrons from one atom to another, resulting in positive and negative ions.

Electronegativity

The tendency of an atom to attract electrons in a chemical bond.

Pauli exclusion principle

No two electrons can occupy the same quantum state simultaneously.

Quantum number (n)

Principal quantum number representing the energy level of an electron.

Bohr model

An early model of the atom where electrons orbit the nucleus in fixed paths.

Schrodinger's theory

Introduced the concept of orbitals, showing electrons exist in cloud-like states rather than fixed orbits.

Bond energy (Eo)

The energy required to break a bond between two atoms.

Coefficient of thermal expansion (αl)

A measure of how much a material expands when heated.

Melting temperature (Tm)

The temperature at which a solid becomes a liquid.

Electron configuration

The distribution of electrons in an atom's orbitals.

Secondary bonding

Attractive forces that arise between dipoles, including dipole-dipole interactions.

Metallic bond

A bond formed by the attraction between positively charged metal ions and the electrons that are free to move around them.

Covalent-Ionic mixed bonding

A type of bonding where both covalent and ionic characteristics are present.

Bond length (r)

The distance between the nuclei of two bonded atoms at minimum energy.