1.
the number of protons in the nucleus of an atom of that element
2.
An atom with the same number of protons and a different number of neutrons
3.
A chart of the elements showing the repeating pattern of their properties
4.
the total number of protons and neutrons in the nucleus of an atom
5.
Smallest particle of an element
6.
a theory that states that all matter is composed of tiny particles called atoms.
7.
A positively charged particle found in the nucleus of an atom
8.
A small particle in the nucleus of the atom, with no electrical charge
9.
A subatomic particle that has a negative charge
10.
The average mass of all the isotopes of an element
11.
An atom or group of atoms that has a positive or negative charge.
