PEG with MW below 600 is a liquid or solid?

PEG with MW below 600 is a liquid or solid?

• A. Gas
• B. Solid
• C. Liquid
• D. Paste

Answer: (C)

The key idea is how molecular weight affects the physical state of polyethylene glycol (PEG). Shorter PEG chains have lower melting points, so at room temperature they behave as liquids, while longer chains raise the melting point and become solids. For PEGs, the practical threshold is around MW 600: below 600, PEG is typically a liquid; above that, it becomes a solid (often waxy). So a PEG with MW under 600 would be a liquid. For example, PEG 400 and PEG 600 are liquids, whereas PEG 1000 is a solid. Therefore, the correct classification is a liquid.

The key idea is how molecular weight affects the physical state of polyethylene glycol (PEG). Shorter PEG chains have lower melting points, so at room temperature they behave as liquids, while longer chains raise the melting point and become solids. For PEGs, the practical threshold is around MW 600: below 600, PEG is typically a liquid; above that, it becomes a solid (often waxy). So a PEG with MW under 600 would be a liquid. For example, PEG 400 and PEG 600 are liquids, whereas PEG 1000 is a solid. Therefore, the correct classification is a liquid.