Students know that each element is made of one kind of atom and that the elements are organized in the periodic table by their chemical properties.

1) There are many websites that have information about the periodic table. Unfortunately, most of them have too much advanced, technical information. The Royal Society of Chemistry hosts a periodic table website that includes relevant information about each of the elements. Some of the information is too technical, but most of it can be used. The location is

http://www.chemsoc.org/viselements/pages/periodic_table.html

A more student-friendly, interactive Periodic Table features brief descriptions, common uses, and information about each element's history at

http://www.bayerus.com/msms/fun/pages/periodic/i_table.html

A funny, animated version of Tom Lehrer’s famous song that includes all the elements of the periodic table is available at

http://www.privatehand.com/flash/elements.html

Students will also enjoy a website that features the elements where they are mentioned in comic books (including original visuals) at

http://www.uky.edu/Projects/Chemcomics/

2) When students take the statewide test covering Grades 4 and 5 science standards, the test booklet will include a reference sheet with the Periodic Table of the Elements. This table can currently be accessed at http://www.cde.ca.gov/ta/tg/sr/cstsciref.asp. Click on 5th Grade Periodic Table link.

3) The columns in the periodic table are called groups. All the elements in a group have similar properties. Most texts highlight the metals and non-metals as examples of groups. The group on the far right can also be useful because of its unusual properties and because students know some of the elements in that group. Discussing this group can also help students understand and correctly use the terms “atom,” “element,” “molecule,” and “compound.”

The group on the far right of the periodic table consists of gases that generally do not react with themselves or with other elements. Helium is a familiar example of these inert, non-reactive gases. Neon, the element just below it, is also familiar because of its use in commercial lighting displays.

Like all elements, the smallest piece of helium or of neon is an atom of helium or neon. A balloon filled with helium has lots of helium atoms in it. The same would be true for neon, argon, krypton, xenon, and radon. Because they are so inert, there are very few compounds that contain any of these gases. They do not readily combine with other elements.

Hydrogen, oxygen, and nitrogen are examples of other elements in the periodic table that naturally occur as gases. Like all elements, the smallest piece of hydrogen, oxygen, or nitrogen is an atom of hydrogen, oxygen, or nitrogen. However, a balloon filled with oxygen has lots of oxygen molecules, and very few or no individual oxygen atoms.

An isolated oxygen atom is so reactive that it will immediately combine with another oxygen atom or atoms of most other elements. A balloon filled with oxygen has lots of oxygen molecules, each molecule consisting of two oxygen atoms connected to each other. This oxygen molecule is not called a compound, because it has two of the same kind of atom. Don’t worry about oxygen being lonely! Because it is so reactive, there are many different compounds that consist of oxygen combined with other elements.