An Unknown Liquid Is Vaporized in a 273-ML Flask by Immersion

question 9

Multiple Choice

An unknown liquid is vaporized in a 273-mL flask by immersion in a water bath at 99 $\degree$ C. The barometric pressure is 753 torr. If the mass of the vapor retained in the flask is 1.362 g, what is its molar mass?

• A) 20.4 g/mol
• B) 40.9 g/mol
• C) 112 g/mol
• D) 154 g/mol
• E) 184 g/mol

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Definitions:

Semipermeable Membrane

A type of membrane that allows certain molecules or ions to pass through by diffusion but not others.

Osmotic Pressure

Amount of turgor that prevents osmosis into cytoplasm or other hypertonic fluid.

Receptor-Mediated Endocytosis

A cellular process where specific molecules are ingested into the cell after they bind to receptors on the cell surface.

Facilitated Diffusion

A process of passive transport, mediated by carrier proteins, allowing molecules to cross the cellular membrane along the concentration gradient without energy expenditure.