Which agent is colorless as a vapor and smells like lemon pledge with an immediate effect?

Which agent is colorless as a vapor and smells like lemon pledge with an immediate effect?

• A. Mustard gas
• B. Lewisite
• C. Chlorine gas
• D. Cyanide gas

Answer: (B)

Recognize agents by how they present in the air: a colorless vapor with a distinctive scent and the time course of its effects helps distinguish them. Lewisite fits here because it is essentially colorless as a vapor and has a notable lemon-like odor that people describe as a lemon polish scent. Importantly, it acts quickly on exposure, causing immediate irritation and pain to skin and eyes, which is a key difference from other blister agents that often have a delayed onset. The other agents don’t match as well. Mustard gas is a blister agent with delayed symptoms and is often described as having a garlic or mustard odor. Chlorine gas has a sharp, choking odor and is not typically described as lemon-scented; it’s also not consistently colorless as a vapor in all conditions. Cyanide gas has a bitter almond odor and acts rapidly, but its aroma is not lemon-like.

Recognize agents by how they present in the air: a colorless vapor with a distinctive scent and the time course of its effects helps distinguish them. Lewisite fits here because it is essentially colorless as a vapor and has a notable lemon-like odor that people describe as a lemon polish scent. Importantly, it acts quickly on exposure, causing immediate irritation and pain to skin and eyes, which is a key difference from other blister agents that often have a delayed onset.

The other agents don’t match as well. Mustard gas is a blister agent with delayed symptoms and is often described as having a garlic or mustard odor. Chlorine gas has a sharp, choking odor and is not typically described as lemon-scented; it’s also not consistently colorless as a vapor in all conditions. Cyanide gas has a bitter almond odor and acts rapidly, but its aroma is not lemon-like.