Undergraduate
Supercooled Liquid (Sodium Acetate)
Video Link: http://www.youtube.com/watch?v=qfsfvl7rcpA
Supercooled Liquids
This is a remarkably effective illustration of the transformation of a supercooled liquid to a solid brought about by one seed crystal. The liquid is the trihydrate of sodium acetate, which melts around 65° C. If allowed to cool undisturbed, it will remain liquid and one crystal of the trihydrate will cause an immediate, exothermic solidification.
MATERIALS
Chemiluminescence (Luminol)
Chemiluminescence (Luminol)
MATERIALS
- Solution 1(in a 1L vol. flask):
Catalysis: Homogeneous and Heterogeneous
CATALYSIS: HOMOGENEOUS AND HETEROGENEOUS
Hydrogen peroxide solution is inert with respect to disproportionation into water and oxygen gas until a catlayst is added to it. Iodide ion produces a slow evolution of oxygen bubbles. The reaction is more rapidly catalyzed by a solid (Ag2O). Bubbles are vigorously evolved at the surface of the catalyst, but at the end of the reaction, the solid catalyst is unchanged.
MATERIALS
Expansion of Water into Steam
Video Link: http://www.youtube.com/watch?v=njgWZjr5nRw
Expansion of H2O(l) to H2O(g)
MATERIALS
- 500mL Erlenmeyer flask
Atomic Structure - Airglow Demonstration (#36)
Iron III Thiocyanate Ion Equilibria
A chemical equilibrium is set up so that with the addition of either reactant, a color change will be observed when the equilibrium shifts to favor either the products or reactants.
MATERIALS
- 3% ammonium thiocyanate solution in dropper bottle
The Effect of Temperature on Equilibrium
The Effect of Temperature on Equilibrium
There are three sealed glass bulbs which contain dinitrgen tetroxide (colorless at room temperature) and nitrogen dioxide (brown at room temperature). When the first bulb is heated, the color will intensify as the dinitrogen tetroxide dissociates. As the second bulb is cooled with liquid nitrogen, the bulb will become colorless. The third bulb will be used as a control.
MATERIALS
Courses
University of Arizona Academic Catalogs
Chemistry and Biochemistry - Academic Department Information