Laboratory Grade

Laboratory grade agents are typically colorless with a consistency ranging from water to motor oil. Salts are colorless to white crystalline solids. Neither solids nor liquids have any significant odor when pure. 

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Grind finely pure laboratory grade, anhydrous potassium fluoride, and heat it in an electrically heated oven at 180-210° store in a desiccator. Before use, dry the powdered salt at 180° for 3 hours and grind again in a warm (ca. 50°) glass mortar. 

Redistil laboratory grade ethylene glycol under reduced pressure and collect the fraction of b.p. 85-90°/7 mm. for use as a solvent for the potassium fluoride. 

These include wastewater cleanup for electroplating (75—78), radioactive processing (79—82), landfill leachate (76,83), and municipal wastewater (84—87) ultrapure water production for electronics-grade (88,89), laboratory-grade (90), and pharmaceutical-grade (91) materials and food processing (qv) (9). 

Laboratory-grade ethylene glycol is redistilled under diminished pressure, and the fraction boiling at 85-90°/7 mm. is used as the solvent for the potassium fluoride. 

They did compromise by using laboratory grade plastic laminate in the instrument room, where chemical spills were rare. It proved to have a higher resistance than anticipated. The monolithic tops, as expected, took a great deal of punishment with no damage. The laboratory operator, though, would have settled happily for the far less expensive ceramic tile. 

Weigh 20 g of homogenized sample into a 300-mL tail-form beaker. Begin recovery samples at this point by fortifying the control tissue matrix samples. Add 120 mL of acetone, and homogenize the mixture for approximately 5 min followed by the addition of 60 mL of laboratory-grade water with another 2 min of homogenization. 

The xylene should be a good, colorless laboratory grade, b.p. 135-140°. Any moisture present may be removed by distilling and discarding the first ro per cent of the distillate. The best aluminium chloride available should be used, for the methy-lation is very unsatisfactory if the catalyst is of an inferior grade. It should be in small pieces, but need not be powdered. 

Laboratory grade agents are typically white, to pale yellow crystalline solids. Some are hygroscopic or deliquescent. They have little or no odor. 

Laboratory grade agents are typically colorless oily liquids or solids. They have little or no odor. Salts of nitrogen vesicants are typically white odorless solids. High concentrations of vesicants can cause eye irritation. Because of the lewisite (C04-A002) component, HL (C03-A010) vapors cause immediate irritation to the eyes, nose, throat, and skin. 

Laboratory grade agents are typically colorless crystalline solids. They have intense, penetrating, and disagreeable odors detectable at very low levels. 

Laboratory grade agents are typically colorless liquids or solids. Depending on the specific agent, liquids may be mobile, viscous, or even waxy in nature. Many solids are salts of the free-base liquid that are colorless to white to beige crystalline materials. In either state, these materials typically have little or no odor when pure. 

Laboratory grade agents are typically colorless to yellow or green liquids or solids. Pure materials are typically odorless. 

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