Soap Emulsifies Hydrocarbons
The first photo shows a stoppered flask with an upper layer of yellow liquid and a lower layer of clear liquid that reflects the yellow liquid. In the second photo, a plastic bottle nozzle is held above the unstoppered flask with the upper layer of yellow liquid and the lower layer that reflects the yellow liquid. The third photo shows the stoppered flask with bubbles in the uppermost layer, white foam in the middle layer, and a darker foam in the bottom layer.
Description: Kerosene and water are shaken together and separate rapidly. Adding liquid soap to the mixture produces a temporary emulsion when the flask is shaken again. The emulsion separates slowly.
Source: UW Card Catalog
Year: N/A Vol: N/A Page: N/A
Keywords: Detergent, Cleaning, Micelle, Oil
Rating: 
Hazard: Some
- Toxicity hazard – oral
- Aspiration hazard
- Flammable liquids
- Skin irritation
- Long term aquatic hazard
- Specific organ toxicity – central nervous system
Effectiveness: Average
- Results are observable with guidance
- Mild effects are seen by audience
- Time to results is low
- Good reliability
Difficulty: Low
- Simple procedures
- Simple manipulations for most to perform
Safety Precautions:
- Gloves required
- Eye protection required
- ABC fire extinguisher on hand
- Avoid exposure to droplets, vapors, and liquids
- Prevent release of reagents to the environment
- Perform in a well-ventilated area
Class: Properties of Solutions, Intermolecular Forces, Physical Chemistry
Division: General, Organic Chemistry
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