Then, in our shortened-period Science class, we completed this worksheet practicing how to find the number of protons, neutrons, and electrons from the information contained in the Periodic Table (specifically atomic number and atomic mass).
The primary points to remember are:
Atomic Number = # of Protons = # of Electrons (in a regular atom)
Atomic Mass = # of Protons + # of Neutrons
(consequently, # of Neutrons = Atomic Mass - Atomic Number)