Atomic Structure and Isotopes

Flashcards covering key concepts in atomic structure, discoveries, and isotopes based on the provided lecture notes.

Atomic Theory

The theory proposed by John Dalton in 1803 that matter is made of atoms, which cannot be created, destroyed, or divided.

Plum Pudding Model

J.J. Thomson's model of the atom which proposed that electrons are scattered within a positively charged 'soup'.

Nuclear Model

Ernest Rutherford's model stating that an atom consists mostly of empty space with a dense nucleus at its center.

Subatomic Particles

Particles that make up atoms; includes protons, neutrons, and electrons.

Isotopes

Atoms of the same element that have the same number of protons but different numbers of neutrons.

Mass Number

The total number of protons and neutrons in an atom's nucleus.

Relative Atomic Mass

A weighted average mass of an element's isotopes relative to 1/12th the mass of carbon-12.

Electron Cloud

The area around the nucleus where electrons are likely to be found, contributing to an atom's overall charge.

Rutherford's Gold Foil Experiment

An experiment that revealed the presence of a nucleus by showing that some alpha particles were deflected.

Electron Shells or Orbitals

Defined paths where electrons orbit around the nucleus at different energy levels.