http://www.youtube.com/watch?v=gCAR5OivA8I
This is a video of the University of Puget Sound's Chemistry Magic Show that I attended. The "wizard," actually one of the Chemistry Professors uses a clock reaction to have the "magical" change of a clear solution into a orange solution into a black solution. The reaction is called "Old Nassau," a nickname for Princeton University, as it has the university's colors and was developed there.
These reactions occur to cause the color changes:
(1) Na2S2O5 + H2O ==> 2 NaHSO3
(2) IO3- + 3 HSO3- ==> I- + 3 SO42- + 3 H+
(3) Hg2+ + 2 I- ==> HgI2
(4) IO3- + 5 I- + 6 H+ ==> 3 I2 + 3 H2O
(5) I2 + starch ==> a blue/black complex
The HgI2 is what accounts for the orange color. When the final reaction occurs, the blue/black complex turns the solution black.
Posted by Dora Moore
Subscribe to:
Post Comments (Atom)
This video was very interesting, it was great to the clock reactions that we have talked about in an actual example. It is amazing how the bright orange substance can turn into such a dark blue/black substance. Without the knowledge of the reaction and how it works, it does almost seem like magic!
ReplyDelete-Alyssa Swanson