1
Q
Atom
A
Smallest unit of matter,has properties of the element
2
Q
Proton
A
Positively charged subatomic particle in the nucleus
3
Q
Neutron
A
Neutral subatomic particle in the nucleus
4
Q
Electron
A
Negatively charged subatomic particle outside of the nucleus
5
Q
Nucleus
A
Center of an atom, has protons and neutrons
6
Q
Mass number
A
Number of protons, identifies the atom
7
Q
Atomic number
A
Number of protons and neutrons
8
Q
Group
A
Column of periodic table, has the same number of valence electrons
9
Q
Period
A
Row on the periodic table
10
Q
Valence electrons
A
Electrons in the outer most energy shell, they determine reactivity
