Chapter 9: Understanding the Atom

Front

What is an atom?

Back

An atom is the smallest unit of matter that retains the properties of an element.

Front

What are the three main particles that make up an atom?

Back

Protons, neutrons, and electrons.

Front

What charge do protons carry?

Back

Protons carry a positive charge.

Front

What charge do electrons carry?

Back

Electrons carry a negative charge.

Front

What is the charge of neutrons?

Back

Neutrons have no charge (they are neutral).

Front

What is the atomic number of an element?

Back

The atomic number is the number of protons in the nucleus of an atom.

Front

What is beta decay?

Back

Beta decay is a type of radioactive decay in which an atomic nucleus emits a beta particle, increasing the atomic number by one.

Front

Who proposed the atomic theory?

Back

John Dalton proposed the atomic theory.

Front

What did J.J. Thomson discover?

Back

J.J. Thomson discovered the electron and proposed the plum pudding model of the atom.

Front

What is the nucleus of an atom?

Back

The nucleus is the central part of an atom, containing protons and neutrons.