Which of the following solvents is most suitable for washing glassware contaminated with organic compounds?

Acetone is the most suitable solvent for washing glassware contaminated with organic compounds due to its excellent solvent properties for a wide range of organic materials. It is a polar aprotic solvent, which means it can effectively dissolve both polar and non-polar organic substances. This characteristic makes it especially effective in removing residues left by various organic compounds.

Additionally, acetone has a low boiling point and evaporates quickly, reducing the amount of time the glassware remains wet, which is beneficial for cleaning processes. Furthermore, acetone is less likely to react with organic contaminants, ensuring that it does not introduce additional complications in the cleanup process.

In contrast, while water is a universal solvent, it is ineffective for washing glassware contaminated with non-polar organic compounds as they do not mix. Hexane can be useful for non-polar substances but is less effective for polar substances. Ethyl alcohol, although it can dissolve some organic compounds, may not be as effective as acetone for a broader range of materials. Thus, acetone stands out for its versatility and effectiveness in cleaning glassware in organic chemistry labs.