Metal Ion Indicator Changes
Description: A titration of Eriochrome black T indicator and Mg solution with EDTA. The end point of this titration is when the Mg-Indicator complex (red) is completely dissociated, and the reactants form the Mg-EDTA complex and free Indicator (blue).
Source: Harris, Daniel Quanitative Chemical Analysis 5th edition
Year: 1999 Vol: N/A Page: 325
Keywords: Titration, Chelation, EDTA, Indicator, Complexation
Rating: 
Hazard: Some
- Toxicity hazard
- Inhalation hazard
- Skin irritation
- Electric shock hazard
Effectiveness: Average
- Somewhat connected conceptually to course material
- Results are observable without guidance
- Secondary effects are seen by audience
- Time to effects is high
Difficulty: Medium
- Procedures with some intermediate steps to result
- Volume-dependent addition for proper results
- Use of mildly reactive substances
- Some careful manipulations required
Safety Precautions:
- Eye protection required
- Gloves required
- Sodium bicarbonate on hand
- Perform in a well-ventilated area
- Absorbent material on hand
- Use UL approved three-prong plug and outlet
Class: Titrations
Division: Analytical Chemistry
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