Early Atomic Theory-Honors Chem

Front

What did J.J. Thomson discover about the atom?

Back

J.J. Thomson provided evidence that an atom contains negatively charged particles (electrons).

Front

Who was the first person to propose a theory about the atom?

Back

Democritus was the first person to propose a theory about the atom.

Front

What varies between isotopes of an element?

Back

Isotopes of an element vary in the number of neutrons and atomic mass.

Front

What particle is found in the nucleus and has no charge?

Back

The neutron is found in the nucleus and has no charge.

Front

Which subatomic particle has a negative charge and is located outside of the nucleus?

Back

The electron is the subatomic particle that has a negative charge and is located outside of the nucleus.

Front

What is the charge of a proton?

Back

A proton has a positive charge.

Front

What is the atomic number of an element?

Back

The atomic number of an element is the number of protons in its nucleus.

Front

What is the mass number of an atom?

Back

The mass number of an atom is the total number of protons and neutrons in its nucleus.

Front

What is an ion?

Back

An ion is an atom or molecule that has a net electrical charge due to the loss or gain of one or more electrons.

Front

What is the difference between an atom and a molecule?

Back

An atom is the smallest unit of an element, while a molecule is a group of two or more atoms bonded together.