Atomic Theory, Nuclear Structure, Mole Conversions, and Light Properties Flashcards

Vocabulary flashcards covering historical atomic models, fundamental forces, nuclear structure, mass and mole conversions, and light properties.

Democritus

A Greek philosopher from 400 BC who discovered the term atom, which means "invisible".

Dalton

An 1800s scientist who discovered that all matter consists of tiny particles called atoms, which are indestructible, unchangeable, characterized by the weight of their atoms, and combine to form new compounds.

Thomson

An 1890s physicist who used cathode ray tube technology to discover the electron and proposed the Plum Pudding Model.

Plum Pudding Model

An atomic model created by Thomson that depicts a positively charged fluid containing corpuscles (electrons).

Rutherford

A 1900s physicist who discovered the nucleus and the electron orbiting the nucleus, leading to the Planetary model.

Bohr

A 1910s physicist who agreed with the Planetary model and discovered that electrons orbit the nucleus in orbits that have a set size and energy.

Schrodinger

A 1920s revolutionary physicist who came up with the atomic model used today, where every electron has its own identity defined by a set of quantum numbers.

Strong Nuclear Force

The force operating between pairs of subparticles (proton-neutron, proton-proton, neutron-neutron) with a range of $1\,fm = 1 \times 10^{-24}\,m$.

Electromagnetic Forces

One of the 4 forces ruling the world, existing between positive ($+$) and negative ($-$) charges.

Weak Nuclear Forces

Forces involved when particles break down during radioactive decay.

Gravitational Pull

The force rule due to mass.

Atomic Number

The number of protons that each element has.

Isotopes

Atoms of the same element that have different masses.

Mass Number

The sum of protons plus neutrons ($\text{protons} + \text{neutrons}$).

Hyphen Notation

A method of writing isotopes specifying the element name followed by a hyphen and mass number, such as Uranium-235.

Nuclear Symbol

A representation of an isotope such as ${}^{235}_{92}\text{U}$, where the superscript indicates the mass number and the subscript indicates the atomic number.

Atomic Mass Unit

A unit ($1\,amu$) defined as exactly $1/12$ the mass of a carbon-12 atom.

Average Atomic Mass

The weighted average of the atomic masses of the naturally occurring isotopes of an element.

Mole

The SI unit for the amount of substance, where $1\,mol$ of anything equals $6.022 \times 10^{23}$ particles.

Avogadro's Number

The quantity $6.022 \times 10^{23}$, representing the number of atoms, molecules, electrons, or ions in one mole.

Mole Conversion Diagram

A conversion scheme showing how to convert between grams and moles using molar mass, and between moles and atoms or molecules using Avogadro's number ($6.022 \times 10^{23}$).

Electromagnetic Radiation

A form of energy that exhibits wavelike behavior as it travels through space.

Electromagnetic Spectrum

All forms of electromagnetic radiation.

Wavelength

Represented by $\lambda$, the distance between corresponding points on adjacent waves.

Frequency

Represented by $\nu$, the number of waves that pass a given point in a specific time, usually one second.

Photoelectric Effect

Refers to the emission of electrons from a metal when light shines on the metal.

Quantum of Energy

The minimum quantity of energy that can be lost or gained by an atom.