Vapor pressure Original Scenario-Based Download PDF

Questions

1. 1.

   A xenochemist aboard a deep-space exploration vessel is testing three synthetic coolant liquids stored at a constant temperature of 298 K in separate, identical sealed reservoirs. Fluid Alpha exhibits extensive intermolecular hydrogen bonding, Fluid Beta interacts primarily via dipole-dipole attractions, and Fluid Gamma interacts solely through weak London dispersion forces, with all three compounds having comparable molar masses. Which statement correctly compares and explains the equilibrium vapor pressures of these coolants at this temperature?

   • A) Fluid Alpha has the highest vapor pressure because hydrogen bonds allow surface molecules to escape into the vapor phase more rapidly than weaker forces.
   • B) Fluid Gamma has the highest vapor pressure because its molecules are held together by the weakest intermolecular forces, requiring the least energy to transition into the gas phase.
   • C) Fluid Beta has a lower vapor pressure than Fluid Alpha because permanent dipole-dipole attractions are substantially stronger than hydrogen bonding networks.
   • D) All three fluids exhibit identical vapor pressures because equilibrium vapor pressure is determined exclusively by reservoir volume rather than molecular interactions.