Atomic Theory and Atoms Retake Practice

Front

Subatomic particles with a positive charge

Back

Protons are subatomic particles found in the nucleus of an atom, carrying a positive electrical charge.

Front

Discovered the nucleus of the atom through the Gold Foil Experiment

Back

Ernest Rutherford conducted the Gold Foil Experiment, which led to the discovery of the atomic nucleus.

Front

All atoms of a particular element have the same number of these

Back

Protons. The number of protons in an atom defines the element.

Front

The most current theory of an atom is the _______ model.

Back

Electron cloud model. This model describes electrons as existing in probabilistic clouds around the nucleus.

Front

Discovered the electron within the atom

Back

J.J. Thomson discovered the electron through his experiments with cathode rays.

Front

The center of an atom, containing protons and neutrons, is called the

Back

Nucleus. The nucleus is the dense central core of an atom.

Front

The negatively charged subatomic particles are called

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Electrons. Electrons orbit the nucleus and have a negative charge.

Front

The atomic number of an element is determined by the number of

Back

Protons. The atomic number uniquely identifies an element.

Front

The mass number of an atom is the sum of its

Back

Protons and neutrons. It represents the total number of nucleons in the nucleus.

Front

Isotopes are atoms of the same element that have different numbers of

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Neutrons. Isotopes have the same number of protons but different mass numbers.