Atomic Theory Vocabulary

Ernest Rutherford

• A New Zealand-born physicist known for his work in nuclear physics and the discovery of radioactive half-life.

• An American chemist who discovered the periodic table of elements.

• A British mathematician famous for his contributions to calculus.

• A German biologist known for his theory of evolution.

John Dalton

• An English chemist, physicist, and meteorologist who is best known for introducing the atomic theory into chemistry.

• A famous physicist known for his work on the laws of motion.

• A chemist who discovered the periodic table of elements.

• An astronomer who developed the theory of relativity.

J.J. Thompson

• An English physicist who discovered the electron and proposed the plum pudding model of the atom.

• A German chemist known for the periodic table.

• An American physicist who developed the theory of relativity.

• A British mathematician famous for his work in number theory.

Electron Cloud

• The region around the nucleus of an atom where electrons are likely to be found.

• A solid structure that contains protons and neutrons.

• A cloud of gas surrounding the atom.

• The area where only neutrons are located.

Frequency

• The measure of how fast an object is moving.

• The number of occurrences of a repeating event per unit of time, often used in the context of waves, such as light or sound.

• The total distance traveled by an object in a given time.

• The amount of energy carried by a wave.

Proton

• A subatomic particle found in the nucleus of an atom, with a positive electric charge.

• A negatively charged particle that orbits the nucleus of an atom.

• A neutral particle found in the nucleus of an atom.

• A particle that is responsible for the chemical properties of an element.

Atomic Mass

• The mass of an atom expressed in grams.

• The mass of an atom, typically expressed in atomic mass units (amu), approximately equivalent to the number of protons and neutrons in the atom.

• The total number of electrons in an atom.

• The weight of an atom in relation to its volume.

James Chadwick

• An English physicist who discovered the neutron.

• A German chemist known for the periodic table.

• An American astronomer who discovered Pluto.

• A French mathematician famous for his work in calculus.

Atomic Number

• The number of neutrons in the nucleus of an atom.

• The number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table.

• The total number of electrons in an atom.

• The mass of an atom measured in atomic mass units.

Electron

• A subatomic particle with a positive electric charge, found in the nucleus.

• A subatomic particle with no electric charge, found in the nucleus.

• A subatomic particle with a negative electric charge, found in the electron cloud surrounding the nucleus.

• A subatomic particle with a negative electric charge, found in the nucleus.