What is the name of the blister agent that causes immediate pain upon contact with skin?

The blister agent that causes immediate pain upon contact with skin is Lewisite. It is a chemical warfare agent that is specifically designed to cause severe damage to the skin and respiratory system, leading to painful blisters and other symptoms. Upon exposure, individuals can experience intense and immediate pain, which distinguishes it from other agents that may have different onset times for their effects.

In contrast, Mustard Gas, another well-known blister agent, causes delayed effects and does not produce immediate pain upon contact. Phosgene is primarily a choking agent that affects the lungs rather than causing blistering. Sarin is a nerve agent that disrupts the normal function of nerves but does not cause blistering or immediate pain upon skin contact. Understanding these differences is crucial for identification and response to various chemical agents in hazardous situations.