Limiting Reagent – Reaction of Magnesium and HCl
Three graduated cylinders with clear liquids and three Petri dishes with metal coils. In the second photo, three Petri dishes with metal coils and different amount of gas in clear liquids.
Description: Equal qualities of magnesium are reacted with unequal quantities of acid. In one, Mg is quickly completely dissolved. In a second, most Mg remains. In a third, Mg barely reacts with the HCl. This is displayed on an overhead projector.
Source: UW Card Catalog
Year: N/A Vol: N/A Page: N/A
Keywords: Magnesium, HCl, Limiting, Projector
Rating: 
Hazard: Some
- Production of flammable gases
- Use of pyrophoric metal
- Flammability hazard
- Skin corrosion hazard
- Inhalation hazard
- Electric shock hazard
Effectiveness: Average
- Results are observable with guidance
- Good connection from demo to course material
- Mild effects are seen by audience
- Reliability is moderate
- Time to results is medium
Difficulty: Some
- Some sequential manipulations
- Some intermediate steps to results
- Simple manipulations for most to perform
- Concentration-dependent additions
Safety Precautions:
- Gloves required
- Eye protection required
- Absorbent materials recommended
- Use of UL approved three-prong plug and outlet
- Perform in a well-ventilated area
- Sand or Class D fire extinguisher on hand
- Avoid exposure to mist or vapors
Class: Gas Production Reaction
Division: General
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