more than meets the eye

Author: Mary Salit
Posted: September 16, 2012 at 1:27PM
Source: The Physics Front collection

There is some unique content beneath the shiny interface and pretty graphics here.  Almost every element has a link to a podcast (and a transcript) describing its history and uses in an approachable narrative form, and links to videos and "resources."

The resources in particular seem like material that could be incorporated into a lesson plan rather than simply used as reference material. In many cases they outline activities which could be done in a laboratory session or as a demonstration. In other cases, such as the reaction of rubidium with water (a little dangerous for an in class demo) they feature videos of the experiment instead.

It is the resources section which differentiates this site from similar ones, and makes it useful for teachers, not just students preparing reports.

• 4D (6-8) #1.  All matter is made up of atoms, which are far too small to see directly through a microscope. The atoms of any element are alike but are different from atoms of other elements. Atoms may stick together in well-defined molecules or may be packed together in large arrays. Different arrangements of atoms into groups compose all substances.
• 4D (6-8) #5.  Scientific ideas about elements were borrowed from some Greek philosophers of 2,000 years earlier, who believed that everything was made from four basic substances: air, earth, fire, and water. It was the combinations of these "elements" in different proportions that gave other substances their observable properties. The Greeks were wrong about those four, but now over 100 different elements have been identified, some rare and some plentiful, out of which everything is made. Because most elements tend to combine with others, few elements are found in their pure form.
• 4D (6-8) #6.  There are groups of elements that have similar properties, including highly reactive metals, less-reactive metals, highly reactive nonmetals (such as chlorine, fluorine, and oxygen), and some almost completely nonreactive gases (such as helium and neon). An especially important kind of reaction between substances involves combination of oxygen with something elseÑas in burning or rusting. Some elements don't fit into any of the categories; among them are carbon and hydrogen, essential elements of living matter.
• 4D (9-12) #1.  Atoms are made of a positive nucleus surrounded by negative electrons. An atom's electron configuration, particularly the outermost electrons, determines how the atom can interact with other atoms. Atoms form bonds to other atoms by transferring or sharing electrons.