1.
The smallest unit of matter that retains the properties of an element
2.
The dense center of an atom containing protons and neutrons
3.
Positively charged subatomic particles found in the nucleus
4.
Negatively charged subatomic particles that orbit the nucleus
5.
Neutral subatomic particles found in the nucleus
6.
A pure substance made of only one type of atom
7.
Atoms of the same element that differ in the number of neutrons
8.
A substance formed when two or more elements are chemically combined
9.
An atom or molecule with a positive or negative charge due to loss or gain of electrons
10.
A chemical bond formed by the transfer of electrons between oppositely charged ions
11.
A chemical bond formed when atoms share pairs of electrons
12.
A group of atoms bonded together, representing the smallest unit of a compound
