Bromination of Saturated and Unsaturated Hydrocarbons
Dehydration of Sugar by Sulfuric Acid
Organic Synthesis With Familiar Materials
Oxidation of Primary, Secondary, Tertiary Alcohols
Underwater Fireworks: Chlorination of Acetylene
Differences in the Miscibility of Organic Alcohols With Increasing Chain Length
Combustion of Cellulose Nitrate (Guncotton)
Different Smells of Carvone Isomers
Distinguishing Between HD and LD Polyethylene
Enviro-bond: Cleaning Oil Spills
Esterification Using a Dean-Stark Trap
IR Demonstration I – Atomic Coupling
IR Demonstration II – Molecular Vibrations
IR Demonstrations III – Molecular Vibrations
Making a Rubber Ball from Latex
Reaction Intermediates in Organic Chemistry
Reducing Sugars and Fehling’s Solution
Rod Climbing by a Polymer Solution
Superabsorbent Polyacrylate Gel
Aniline Hydrochloride-Formaldehyde Polymer
Relative Reactivity of Reducing Agents
Electrophilic Aromatic Substitution Reaction/EAS Reaction
Reactivity of Alkanes vs. Aromatic Compounds
Optical Activity of Racemic Mixtures With Limonene
Relationship of Absorbed Light to Observed Color
Density and Miscibility of Liquids
Extraction of Copper Ions from Solution with Orform®
Gel Formation with Sodium Alginate and Calcium Chloride
Hydrolysis of T-Butyl Chloride: A Lecture and Lab Experiment
Rotating Rainbows
Description: Karo syrup and water are placed on the overhead projector between crossed polarizers. As the upper polarizer is rotated over the Karo syrup and the lower polarizer, the relative angle between the plane polarizer orientation changes, thereby allowing specific wavelength ranges of color to pass through the polarizers from the white light emitted by the overhead projector lamp. This effect is seen when the liquid placed in the beaker between the polarizers has a structure which rotates polarized light. This kind of molecule is called optically active. Water is not an optically active molecule so changing the relative angle between the polarizer planes does not affect the properties of the light that passes through it.
Source: Journal of Chemical Education
Year: 1999 Vol: 76 Page: 1233 – 1236
Keywords: Isomers, Stereoisomers
Rating: 
Hazard: Low
- Electric shock hazard
- Breakage hazard
Effectiveness: Good
- Results are clearly observable without guidance
- Good connection from demo to course material
- Low failure rate
- Time to results is low
- Good effects are seen by audience
Difficulty: Low
- Simple procedures
- Simple manipulations for most to perform
- Use of glass surfaces, handle with care
Safety Precautions:
- Eye protection required
- Use of UL approved three-prong plug and outlet required
Class: Organic Chemistry, Molecular Structure
Division: General, Organic Chemistry
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