http://www.ck12.org Chapter 2. Matter
FIGURE 2.115
Chemical Properties of Halogens
The halogens are among the most reactive of all elements, although reactivity declines from the top to the bottom of
the halogen group. Because all halogens have seven valence electrons, they are “eager” to gain one more electron.
Doing so gives them a full outer energy level, which is the most stable arrangement of electrons. Halogens often
combine with alkali metals in group 1 of the periodic table. Alkali metals have just one valence electron, which they
are equally “eager” to donate. Reactions involving halogens, especially halogens near the top of the group, may be
explosive. You can see some examples in the video at the URL below. (Warning:Don’t try any of these reactions at
home!)
http://www.youtube.com/watch?v=mY7o28-l_WU (1:00)
MEDIA
Click image to the left for use the URL below.
URL: http://www.ck12.org/flx/render/embeddedobject/54896