A flask that contains hexane (d = 0.66 g/mL) and water (d = 1.0 g/mL); these liquids do no mix together. Different materials are added to the flask. Identify the material indicated by the square object in the figure below.

• A. Polystyrene (1.05 g/mL)
• B. Low-density polyethylene (0.91 g/mL)
• C. Polyurethane (0.06 g/mL)
• D. Polychloroprene (1.23 g/mL)

Answer: (C)