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Atomic Number, Ions and Isotopes

Atomic Number, Ions and Isotopes

Author: Katie Smith

The purpose of this packet is to compare two otherwise alike atoms when the number of protons, neutrons or electrons is different.

This packet includes several slide shows that will explain atomic numbers and mass numbers, and help you determine the number of protons, neutrons or electrons in a molecule.

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In this packet, we will take a closer look at an atom.  We'll compare atoms that are otherwise alike, but with a different number of protons, then move on to different numbers of neutrons and electrons.

At this point, you should have an idea of what an atom is.  You have probably looked a bit at the periodic table, but if you're not familiar with how to use it, you'll want to find a list with the names of the elements, their symbols and their atomic numbers (check in your textbook!)   As you go through this packet, watch out for the terms atomic number, mass number, isotope, ion, cation and anion.

Atomic Number, Mass Number, and Ions

This slideshow will review atomic number, mass number and ions. The second slide shows a table of contents if you wish to skip around

Example Problems

At the end of each slide, stop and try to work through the problem before reviewing the solution on the next slide.

How to Write a Full Atomic Symbol