Balloon Races – Ionization of Hydrochloric Acid and Acetic Acid
Common Ion Effect with Lead Iodide
Effect of Ionic Strength on Ion Dissociation
Precipitating Silver with Chromate and Chloride Ions
Precipitating Sodium Chloride from Its Solution
Effect of Ionic Strength on Ion Dissociation
Description: The effect of ionic strength on dissociation is tested using an Iron (III) Thiocyanate complex. Mixing a solution of Iron (III) and KSCN produces a pale red solution. Adding potassium nitrate to the solution causes the color to fade.
Source: Harris, Daniel C. Quanitative Chemical Analysis 2nd ed.
Year: 1999 Vol: N/A Page: 177
Keywords: Iron (III) Thiocyanate complex, Potassium Nitrate, Ionic strength, Dissociation
Rating: 
Hazard: Medium
- Acute toxicity hazard – oral, inhalation, dermal
- Corrosive to metals
- Serious eye damage
- Oxidizing liquids
- Aquatic toxicity hazard
- Skin corrosion hazard
Effectiveness: Good
- Good connection from demo to course material
- Results are clearly observable without guidance
- Clear contrast between systems behavior
- Low failure rate
- Time to results is low
Difficulty: Medium
- Some concerted or timed manipulations
- Use of toxic substances
- Some physical manipulations
Safety Precautions:
- Eye protection required
- Gloves required
- Absorbent materials on hand
- Avoid exposure to mists, dusts, or vapors
- Prevent release of reagents to the environment
- Sodium bicarbonate on hand
Class: Dissociation, Solubility, Equilibrium
Division: Analytical Chemistry
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