HChem, Unit 2 Vocabulary

Gold foil experiment

• An experiment conducted by Ernest Rutherford that led to the discovery of the atomic nucleus.

• A method used to determine the density of gold.

• A technique for measuring the speed of light.

• An experiment that proved the existence of electrons.

Ernest Rutherford

• A physicist who discovered the nucleus of the atom through the gold foil experiment.

• A chemist known for his work on the periodic table.

• An astronomer who studied the motion of planets.

• A biologist who developed the theory of evolution.

Quantum theory

• A theory in physics that describes the behavior of large-scale objects.

• A theory in physics based on the principle that matter and energy have the properties of both particles and waves.

• A theory in physics that only applies to classical mechanics.

• A theory in physics that explains the motion of planets.

Quarks

• Elementary particles and a fundamental constituent of matter, which combine to form protons and neutrons.

• Particles that orbit the nucleus of an atom.

• The smallest unit of a chemical element.

• Subatomic particles that carry a positive charge.

Mass number

• The total number of protons and neutrons in an atomic nucleus.

• The total number of electrons in an atom.

• The number of protons in the nucleus only.

• The sum of protons and electrons in an atom.

Average atomic mass

• The total mass of an element's isotopes combined.

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

• The mass of the most abundant isotope of an element.

• The average mass of all atoms in a molecule.

Electron

• A positively charged particle found in the nucleus of an atom.

• A subatomic particle with a negative electric charge, found in all atoms and acting as the primary carrier of electricity in solids.

• A neutral particle that contributes to the mass of an atom.

• A particle that orbits the nucleus and has no charge.

Subatomic particles

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

• Particles that are larger than an atom, such as molecules and compounds.

• Particles that are found only in the nucleus of an atom.

• Particles that are responsible for chemical reactions in atoms.

Nuclear symbol

• A notation that indicates the composition of an atomic nucleus, showing the element symbol, atomic number, and mass number.

• A representation of the chemical bonds in a molecule.

• A symbol used to denote the energy levels of electrons in an atom.

• A diagram that illustrates the arrangement of protons and neutrons in an atom.

Crest

• The lowest point of a wave.

• The highest point of a wave.

• The speed of a wave.

• The distance between two waves.