Arsenic trifluoride, with the chemical formula AsF3, is a chemical compound composed of arsenic (As) and fluorine (F) atoms. It is a colorless, toxic gas at room temperature, but it can also exist as a white solid when cooled to very low temperatures.

Arsenic trifluoride is a highly reactive and toxic compound with several key properties and uses, including:

1. Chemical Reagent: It is used as a chemical reagent in various chemical reactions, particularly in the synthesis of other arsenic compounds.
2. Semiconductor Manufacturing: Arsenic trifluoride is used in the semiconductor industry for certain etching processes and as a doping agent.
3. Glass and Ceramic Industry: It is employed as a glass etchant and in the production of some ceramic materials.
4. Pesticide: Historically, arsenic-based compounds, including arsenic trifluoride, were used as pesticides and insecticides. However, their use has been significantly reduced due to their toxicity and environmental concerns.

Arsenic trifluoride is highly toxic and poses health risks if mishandled or misused. It should be handled with extreme care in a well-ventilated area, and appropriate personal protective equipment should be used to prevent exposure.

Due to its reactivity and toxicity, arsenic trifluoride requires careful handling and is used mainly in specialized industrial processes where its unique properties are required. Its use in pesticides has diminished significantly over the years due to the availability of safer alternatives.