2.28. Atoms http://www.ck12.org
2.28 Atoms
- Describe atoms and how they are related to elements.
- Identify the three main subatomic particles that make up atoms.
What could this hilly blue surface possibly be? Do you have any idea? The answer is a single atom of the element
Cobalt. The picture was created using a scanning tunneling microscope. No other microscope can make images of
things as small as atoms. How small are atoms? You will find out in this lesson.
What Are Atoms?
Atomsare the building blocks of matter. They are the smallest particles of an element that still have the element’s
properties. Elements, in turn, are pure substances—such as nickel, hydrogen, and helium—that make up all kinds
of matter. All the atoms of a given element are identical in that they have the same number of protons, one of
the building blocks of atoms (see below). They are also different from the atoms of all other elements, as atoms
of different elements have different number of protons. For an entertaining introduction to atoms by Bill Nye the
Science Guy, watch the video at this URL:
http://www.youtube.com/watch?v=cnXV7Ph3WPk (6:37)
MEDIA
Click image to the left for use the URL below.
URL: http://www.ck12.org/flx/render/embeddedobject/54885