Effects on boiling point, viscosity and surface tension Transitional Reasoning Download PDF

Questions

1. 1.

   A chemistry student investigates three unknown pure liquids—P, Q, and R—having similar molar masses at 20 °C. Liquid P takes the longest duration to drain through a vertical capillary tube and forms spherical beads on a nonpolar surface, whereas Liquid R flows through the tube almost immediately and spreads out into a flat film. Based on these observations, which statement correctly compares the macroscopic properties and intermolecular forces of the liquids?

   • A) Liquid R possesses the strongest intermolecular forces because rapid flow through the capillary tube indicates minimal resistance between molecules.
   • B) Liquid P has the highest boiling point and strongest intermolecular forces because stronger cohesive forces increase both viscosity and surface tension.
   • C) Liquid R has a higher surface tension and higher boiling point than Liquid P because quick drainage reflects greater net cohesion in the liquid bulk.
   • D) Liquid P has the lowest boiling point because its high surface tension allows molecules to escape into the vapor phase more readily.