Development of Atomic Structure and Nucleosynthesis

Vocabulary flashcards covering key terms and concepts from atomic structure development and nucleosynthesis.

Atomos

Greek word meaning "indivisible"; early idea of matter as tiny, indivisible particles.

Democritus (440 BCE)

First proposed that matter is made of small, indivisible particles surrounded by empty space.

Solid-Sphere Model

John Dalton’s (1803) view of the atom as a uniform, indestructible solid sphere.

Plum Pudding Model

J. J. Thomson’s (1904) model in which electrons are embedded in a positive "pudding" matrix.

Nuclear Model

Ernest Rutherford’s (1911) model with a tiny, dense, positively charged nucleus and mostly empty space.

Planetary Model

Niels Bohr’s (1913) model where electrons orbit the nucleus in fixed energy levels.

Quantum Model

Erwin Schrödinger’s (1926) model describing electron positions as probability clouds (orbitals).

Nucleosynthesis

Thermonuclear process that creates new atomic nuclei from pre-existing protons and neutrons.

Big Bang Nucleosynthesis

Primordial formation of H, He, and small amounts of Li during the first minutes after the Big Bang.

Stellar Nucleosynthesis

Creation of elements inside stars via nuclear fusion, building heavier nuclei from lighter ones.

Supernova Nucleosynthesis

Production of the heaviest elements during massive star explosions, dispersing them into space.

Proton (p⁺)

Positively charged subatomic particle located in the nucleus; defines atomic number.

Neutron (n⁰)

Neutral subatomic particle in the nucleus; contributes to mass number but not charge.

Electron (e⁻)

Negatively charged subatomic particle occupying regions outside the nucleus.

Atomic Number (Z)

Number of protons in an atom’s nucleus; determines the chemical element.

Mass Number (A)

Total number of protons and neutrons in an atom’s nucleus.

Isotope

Atoms of the same element (same Z) that differ in mass number (A) due to varying neutrons.

Ion

Atom or molecule that has gained or lost electrons, acquiring an electric charge.

Cation

Positively charged ion formed by the loss of one or more electrons.

Anion

Negatively charged ion formed by the gain of one or more electrons.