A sealed flask initially contains 200 mL of an aqueous solution of ethanol, C₂H₅OH
PHYSICS · Multi-part · ISC · Chemistry · Physics · Behaviour of Perfect Gases and Kinetic Theory of Gases
Problem
A sealed flask initially contains 200 mL of an aqueous solution of ethanol, C₂H₅OH, at 10 °C. The flask is slowly warmed to 60 °C while no evaporation occurs. Ethanol is a polar molecular compound that hydrogen-bonds with water and remains as intact molecules in solution.
(a) Describe the arrangement and orientation of ethanol molecules relative to water molecules that should be shown in a particle diagram of the solution at 10 °C, focusing on hydrogen-bonding interactions.
(b) In a second diagram of the same solution at 60 °C, qualitatively describe any expected changes in average intermolecular spacing and the prevalence of hydrogen bonds. Explain why these changes are consistent with the temperature increase.