Trichloroethane vs. Trichloroethene

Attribute	Trichloroethane	Trichloroethene
Chemical Formula	C2H3Cl3	C2HCl3
Boiling Point	73.5°C	87.2°C
Melting Point	-73.5°C	-85.2°C
Density	1.46 g/cm3	1.46 g/cm3
Solubility in Water	0.8 g/L	1.2 g/L

Introduction

Trichloroethane and trichloroethene are two commonly used chemicals in various industrial applications. While they may sound similar, they have distinct differences in terms of their chemical properties, uses, and potential health effects. In this article, we will compare the attributes of trichloroethane and trichloroethene to provide a better understanding of these two chemicals.

Chemical Structure

Trichloroethane, also known as 1,1,1-trichloroethane, has a chemical formula of C₂H₃Cl₃. It is a colorless liquid with a sweet odor and is commonly used as a solvent in various industrial processes. On the other hand, trichloroethene, also known as trichloroethylene, has a chemical formula of C₂HCl₃. It is a colorless liquid with a sharp, sweet odor and is primarily used as a solvent for degreasing metal parts.

Physical Properties

Trichloroethane has a boiling point of 74.1°C and a melting point of -107.4°C. It is relatively stable under normal conditions and is not very reactive. Trichloroethene, on the other hand, has a boiling point of 87.2°C and a melting point of -86.7°C. It is more volatile than trichloroethane and can easily evaporate into the air.

Uses

Trichloroethane is commonly used as a solvent in the manufacturing of adhesives, paints, and coatings. It is also used as a cleaning agent for electronic components and precision instruments. Trichloroethene, on the other hand, is primarily used as a degreasing agent in the metalworking industry. It is also used as a solvent for removing grease and oil stains from fabrics.

Health Effects

Exposure to trichloroethane can cause irritation of the skin, eyes, and respiratory tract. Prolonged exposure to high levels of trichloroethane may lead to dizziness, headaches, and nausea. Trichloroethene, on the other hand, is classified as a probable human carcinogen by the International Agency for Research on Cancer (IARC). It has been linked to an increased risk of liver and kidney cancer in humans.

Environmental Impact

Trichloroethane is considered to be moderately toxic to aquatic organisms and can bioaccumulate in the food chain. It is also known to persist in the environment for a long time, leading to potential contamination of water sources. Trichloroethene, on the other hand, is highly volatile and can easily contaminate groundwater through spills or improper disposal. It is a major concern for environmental regulators due to its potential to cause long-term harm to ecosystems.

Regulatory Status

Trichloroethane is regulated by various environmental agencies due to its potential health and environmental risks. It is subject to strict handling and disposal regulations to minimize its impact on human health and the environment. Trichloroethene, on the other hand, is classified as a hazardous air pollutant under the Clean Air Act and is subject to strict emission controls to reduce its impact on air quality.

Conclusion

In conclusion, trichloroethane and trichloroethene are two chemicals with distinct differences in terms of their chemical properties, uses, and potential health effects. While trichloroethane is commonly used as a solvent in various industrial applications, trichloroethene is primarily used as a degreasing agent in the metalworking industry. Both chemicals have potential health and environmental risks, and it is important to handle them with care to minimize their impact on human health and the environment.