Page 246 - Demo

Safety Reference
Flinn Method #3, continued 4a
Only after all pieces of metal are gone, slowly add an equal volume of water to the mixture. Neutralize with 1 M hydrochloric acid.
No metals left
5a
Flush the neutralized mixture down the drain with a 20-fold excess of water.
Procedure B: Potassium Metal
1b
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Perform this procedure in a fume hood. Wear chemical splash goggles, chemical-resistant gloves, and a lab coat or chemical-resistant apron.
2c
Add small increments of leftover metal (1–2 g) to 1 L of cold water (for calcium) or dilute (1 M) hydrochloric acid (for magnesium). Stir the mixture until all the metal has dissolved.
244
Procedure C: Calcium and Magnesium Metal
1c
1M HCl
3c
Using pH paper, neutralize to pH 7 with 3 M sodium hydroxide.
4c
pH Paper
3M NaOH
Perform this procedure in a fume hood. Wear chemical splash goggles, chemical-resistant gloves, and a lab coat or chemical-resistant apron.
2b
Place small pieces of leftover potassium metal in a 500-mL beaker and cover with mineral oil.
Flush the solution down the drain with a 20-fold excess of water.
FLINN METHOD
#4a Picric Acid
3b
Slowly add tert-butyl
alcohol (at least 21 mL
per g potassium) to the
metal at a rate to cause
a reasonable hydrogen
evolution. Stir the reac-
tion mixture until all
the pieces of metal have dissolved.
t-Butyl Alcohol
Picric acid is explosive when dry. Do not touch or handle. Picric acid cannot be disposed of by untrained personnel. You must contact a commercial waste disposal service, the local bomb squad, or fire department. Bouin’s solution contains picric acid; treat it just as care- fully as pure picric acid.
Examples
Picric acid, Bouin’s solution
Overview
Picric acid is normally sold containing 10–15% water, and in this state it is relatively safe to handle. However, dry picric acid is very explosive. The explosion can be initiated by friction, shock, or sudden heating. Picric acid also reacts with metals to form explosive metal picrates which are highly sensitive to detonation. Do not attempt to dispose of picric acid by chemical means. This procedure merely provides a means to wet the picric acid to decrease its hazards.
Procedure
1
Wear a full face shield, chemical-resistant gloves, and a lab coat or chemical-resistant apron.
FLINN METHOD #4a continued on next page.
4b
Only after all pieces of potassium are gone, slowly add an equal volume of water to the reaction mixture. Neutralize with 1 M hydrochloric acid.
5b
1M HCl
No metals left
Flush the neutralized mixture down the drain with a 20-fold excess of water.
Please...Read the Narratives
Important narratives precede these specific chemical disposal methods! Please read each narrative carefully! Do not use these procedures if you are not comfortable with the chemistry. Do not use these procedures without first consulting with your local government regulatory officials. These procedures may not be used in some jurisdictions. All procedures involve some hazards and risks. Once again...read the narratives that precede these specific chemical disposal methods.