Chloroform is slowly oxidised by air in the presence of light to form an extremely poisonous gas known as ______

The correct answer is Phosgene.

Key Points

• Chloroform, when exposed to air and light, is oxidized to form phosgene, a highly toxic gas.
• Phosgene is a colorless gas with a suffocating odor, resembling that of musty hay or green corn.
• It was used as a chemical weapon during World War I due to its lethal properties.
• Phosgene exposure can lead to severe respiratory damage and is potentially fatal even at low concentrations.

Additional Information

• Chloroform (CHCl₃)
  • A volatile, colorless liquid with a slightly sweet taste and odor.
  • Historically used as an anesthetic but discontinued due to its harmful effects on the liver and potential to cause cardiac arrhythmias.
• Oxidation Reaction
  • A chemical reaction where a substance loses electrons, often associated with the addition of oxygen or the loss of hydrogen.
  • In the case of chloroform, oxidation in the presence of light leads to the formation of phosgene.
• Chemical Weapons
  • Substances designed to cause death or harm through toxic properties.
  • Phosgene, being one of the first chemical warfare agents, caused significant casualties during World War I.
• Safety Precautions
  • Proper storage in dark, well-ventilated areas to minimize exposure to air and light.
  • Use of personal protective equipment (PPE) to avoid inhalation or skin contact.