Equilibrium Between Nitrogen Dioxide and Dinitrogen Tetroxide
Effect of Pressure on Melting Point of Ice
The Liquid Phase of Carbon Dioxide
Vapor Pressure of Pure Liquids
Getting Colder: Freezing-Point Depression
Getting Hotter: Boiling-Point Elevation by Non-Volatile Solutes
Osmotic Pressure of a Sugar Solution
Vapor Pressure of Solutions – Raoult’s Law
Boiling Two Liquids at Room Temperature
Salting Out: Making Liquids Immiscible
Electrolysis of Potassium Iodide
Hydrogen Ion Concentration Cell
Acid-Base Properties of Amino Acids
Electrical Conductivity of Liquids and Solutions
Instrumental Recording of a Titration Curve
A Visual Demonstration of Raoult’s Law
Concentration Cell
Description: Two identical half cells are set up using 1.0 M copper ion and copper metal. Zero volts are developed when a salt bridge is put in. One of the solutions is drastically diluted with water. Now a voltage is obtained, displayed on the big voltmeter. This experiment may also use silver nitrate, and chloride is used to precipitate silver ions from one of the half cells.
Source: UW Card Catalog, Shakhashiri, B.Z. Chemical Handbook for Teachers
Year: 1992 Vol: 4 Page: 140 – 143
Keywords: Voltmeter, Electrochemical cell, Potential, Concentration, Copper
Rating:
Hazard: Some
- Acute toxicity hazard
- Aquatic toxicity hazard
- Electric shock hazard
Effectiveness: Good
- Results are clearly observable with guidance
- Good connection from demo to course material
- Experiment addresses preconceived notions
- Secondary observations
Difficulty: Medium
- Procedures with intermediate steps to results
- Volume-dependent addition for proper results
- Use of scientific instrumentation
Safety Precautions:
- Eye protection required
- Gloves required
- Use of UL approved three-prong outlet and plug required
- Absorbent material on hand
- Prevent release of reagents to the environment
Class: Electrochemistry
Division: General, Physical Chemistry
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