A nerve agent is best classified as which type of chemical?

• A. Chlorine-based acids
• B. Noble gases
• C. Phosphorus containing organic chemicals
• D. Inert solids

Answer: (C)

Nerve agents are organophosphorus compounds—phosphorus-containing organic chemicals. Their defining feature is a phosphorus atom bonded to organic groups, and their deadly action comes from inhibiting acetylcholinesterase, the enzyme that breaks down acetylcholine. When this enzyme is blocked, acetylcholine accumulates at nerve endings, causing a surge of cholinergic effects that can rapidly compromise the respiratory and nervous systems. Classic examples include sarin, soman, tabun, and VX, all of which are phosphorus-containing organic chemicals.

This classification makes sense because chlorine-based acids refer to chlorine-containing agents (like chlorine gas), noble gases are inert and nonreactive, and inert solids are not reactive chemicals. So the nerve agent’s type is phosphorus-containing organic chemicals.