Test of Purity of Chloroform:
Chloroform has transparent and colorless, neutral to test paper, non-irritating when inhaled, and should evaporate entirely, leaving no residue or smell on a glass surface. Pure chloroform has boiling point 61-620C.
Physical Purity: CHC13 is a colorless liquid having a boiling point of 62°C. Pure chloroform is boiled & distilled at 62°C. If any impurities are mixed with it, its boiling point also varies-chloroform boils at a higher temperature than 620C.
Chemical Purity: To assure purity of chloroform. AgNO3 is used. In presence of O2, chloroform produces phosgene gas and HCl. AgNO3 reacts with HCl and produce white precipitant of AgCl.
AgNO3 + HCl = AgC1↓ (white) + HNO3
Use of Chloroform:
- It is used as an anesthetic in surgery. But it has harmful effects on the liver & the excessive use of it may threaten the patient’s life—because the difference between anesthetic dose & a lethal dose of it is very less. So, at present, it is not widely used in anesthesia.
- As an excellent solvent, it is used in wax, fats oils, resin & alkaloid industries.
- It is used as an anti-rodent agent.
- In a laboratory, it is used as a reagent & solvent.
- Used as raw material for chloropicrin & in aromatization of foul-smelling drugs.