http://www.ck12.org Chapter 2. Matter
2.56 Noble Gases
- Identify the noble gases.
- List properties of noble gases.
- Explain the nonreactivity of noble gases and how it is related to the octet rule.
Okay, helium balloons are light, but they’re not that light! This fanciful picture serves to make the point that helium
is one of the lightest elements. Helium belongs to a group of elements called the noble gases.
What Are Noble Gases?
Noble gasesare nonreactive, nonmetallic elements in group 18 of the periodic table. As you can see in the periodic
table inFigure2.117, noble gases include helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon
(Rn). All noble gases are colorless and odorless. They also have low boiling points, explaining why they are gases
at room temperature. Radon, at the bottom of the group, is radioactive, so it constantly decays to other elements. For
an excellent overview of the noble gases, watch the video at this URL: