Untitled Flashcards Set

Atom

The basic unit of matter, described by Dalton as a sphere.

Subatomic Particles

Particles smaller than an atom, including electrons, protons, and neutrons.

Plum Pudding Model

Thomson's model of the atom where electrons are distributed in a positive 'soup'.

Cathode Ray Tube Experiment

Experiment by Thomson that led to the discovery of electrons.

Charge of an Electron

Discovered by Millikan, it is negative.

Oil Drop Experiment

Experiment by Millikan to determine the charge of an electron.

Nucleus

The dense center of an atom, discovered by Rutherford.

Gold Foil Experiment

Experiment by Rutherford that revealed the existence of a nucleus within an atom.

Energy Levels

Bohr's concept where electrons orbit the nucleus in defined shells.

Valence Electrons

Electrons in the outermost shell that determine an atom's chemical properties.

Ion

An atom that has gained or lost electrons, resulting in a positive or negative charge.

E-dot Diagram

A diagram that shows valence electrons around the element's symbol.

Isotopic Notation

A way to represent isotopes, formatted as A (mass number) over Z (atomic number) next to the chemical symbol.

Average Atomic Mass

Calculated using the percentages and masses of isotopes present in nature.

Electromagnetic Spectrum

The range of all types of electromagnetic radiation, including visible light.

Ground State

The lowest possible energy state of an atom.

Excited State

When an atom absorbs energy and electrons move to a higher energy level.

Emission Spectrum Lines

The spectrum of light emitted by energized atoms when electrons return to a lower energy level.

Wavelength

The distance between two consecutive crests or troughs of a wave.

Frequency

The number of wavelengths that pass a given point in a certain period of time.

Planck's Constant

The constant used to calculate the energy of a photon, approximately 6.626 x 10^-34 J*s.

Dimensional Analysis

A method for converting between units using conversion factors.

Prefixes for Measurement

Units of measure that indicate multiples (Tera, Mega, Kilo) or submultiples (deci, centi, milli, micro, nano).