8PS Unit 2: Atomic Structure and the Periodic Table

Front

atom

Back

Basic unit of matter

Front

atomic model

Back

The smallest unit of an element, consists of protons and neutrons in a nucleus orbited by a number of electrons

Front

proton

Back

A subatomic particle that has a positive charge and that is found in the nucleus of an atom

Front

neutron

Back

A subatomic particle that has no charge and that is found in the nucleus of an atom

Front

electron

Back

A subatomic particle that has a negative charge

Front

nucleus

Back

Center of an atom

Front

atomic number

Back

The number of protons in an atom

Front

mass number

Back

The total number of protons and neutrons in the nucleus of an atom

Front

average atomic mass

Back

Weighted average of the atomic masses for the isotopes of an element

Front

element

Back

A pure substance made of only one kind of atom