Which of the following wastes is not classified as inorganic waste?

• A. Waste containing mercury
• B. Waste containing lead
• C. Waste containing arsenic
• D. Waste containing acetonitrile

Answer: (D)

Wastes are categorized as inorganic or organic mainly by whether they contain carbon-hydrogen bonds. Organic wastes are carbon-containing compounds, often solvents, while inorganic wastes are elements or compounds that lack a carbon framework.

Waste containing mercury, lead, or arsenic is considered inorganic because these are metals or metal compounds with little to no carbon structure. Acetonitrile, on the other hand, is a carbon-containing organic solvent (CH3-CN), so it falls into the organic waste category.

Therefore, acetonitrile is not classified as inorganic waste.