1. How do structures of atoms Differ?
Protons = the atomic # of an element
Protons give the element it’s identity
Protons are given the identity Z number
Identify each element
Z=2, Z=45, Z=23
Isotopes are atoms of an element with the same # of protons, but different # of neutrons.
The Mass number is the number of protons + the number of neutrons.
Mass # is given the identity A number

2. How do structures of atoms differ?
Isotopic Symbol A Z
A = Mass # (p+n)
Z = atomic # (p)
A-Z= # of neutrons
X is the element’s symbol from the periodic table

3. Section 2 A Guided Tour of the Periodic Table
Chapter 4
Isotopes