1.
The dense center of the atom that contains protons and neutrons.
2.
The number of protons in an atom; it identifies the element.
3.
The total number of protons and neutrons in an atom’s nucleus.
4.
Atoms of the same element that have different numbers of neutrons.
5.
The divisions within an energy level (s, p, d, f) that describe the shape of orbitals.
6.
The weighted average mass of all the naturally occurring isotopes of an element
7.
The number of valence electrons that a neutral nitrogen has
8.
The electrons found in the outermost energy level
9.
A horizontal row on the periodic table
10.
A vertical column on the periodic table
