An Unknown Nonelectrolyte and Nonvolatile Compound Is Dissolved in Enough

question 136

Multiple Choice

An unknown nonelectrolyte and nonvolatile compound is dissolved in enough pure water to make 348 mL of solution. The vapour pressure above the solution drops from 198.7 mbar to 196.7 mbar when 100.0 g of the compound is dissolved at constant temperature. Determine the molar mass of the unknown compound. Assume no change in volume occurs upon dissolution.

• A) 689 g mol^-1
• B) 342 g mol^-1
• C) 180 g mol^-1
• D) 509 g mol^-1
• E) 243 g mol^-1

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Definitions:

UCS And CS

Unconditioned Stimulus (UCS) is a stimulus that naturally and automatically triggers a response without prior learning; Conditioned Stimulus (CS) is a previously neutral stimulus that, after becoming associated with the unconditioned stimulus, eventually comes to trigger a conditioned response.

Coyotes

Medium-sized carnivores native to North America, known for their adaptability to various habitats, including urban areas, and often characterized by their distinctive howl.

Research

The systematic investigation into and study of materials and sources to establish facts and reach new conclusions.