Bromine, test for

The double bond of tetrachloroethene is undetectable in the bromine test for unsaturation. Give a plausible explanation... 

Transfer the pot residues from the distillation of spearmint and/or caraway oil to the container for nonchlorinated organic wastes. After performing the prescribed tests on your distillate, put the isolated natural products into appropriately labeled containers. Place the dichloromethane solution from the bromine test for unsaturation in a container for halogenated organic liquids put the manganese dioxide from the Baeyer test for unsaturation in a container for heavy metals. Neutralize and then filter any excess 2,4-dinitrophenylhydrazine solution. Put the filter cake in the container for nonhazardous solids. Flush the filtrate as well as filtrates obtained from recrystallization down the drain. 

Neutralize the residue remaining in the stillpot with 10% aqueous hydrochloric acid then flush it down the drain. Place the dichloromethane solution from the bromine test for unsaturation in a container for halogenated organic liquids put the manganese dioxide from the Baeyer test for unsaturation in a container for heavy metals. 

Chemical Tests. Add several crystals ( 5 mg) of the fra s-dnnamic add to 1 mL of 5% sodium bicarbonate on a watch glass. Does evolution of CO2 indicate the presence of a carboxylic add Does the material give a positive bromine test for unsaturation (see Chapter 9). 

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