Why Do Liquids Evaporate Intermolecular Rates

INTRODUCTION The objective in this experiment is to better understand why liquids evaporate at different rates. In doing so, investigation of the factors that determine the intensity of the intermolecular forces by the rate of evaporation must be obtained in the following seven liquids: methanol, ethanol, propanol, butanol, water, pentane, and acetone. Intermolecular forces are forces that exist between molecules whereas intramolecular forces are the forces that hold atoms together within a molecule. Each of the seven liquids consists of intermolecular force energy; hydrogen bonding, dipole-dipole bonding, or london dispersion bonding. The type of intermolecular forces in a molecule is a result of bond polarity, which is determined by the electronegativity differences, and molecular shape, that is determined by an electron-dot structure. A hydrogen bond is a bond that consists of an attraction force between a hydrogen and an electronegative atom of

After performing the investigation, it was concluded that each of the seven liquids will have different evaporation rates based upon strength and type of their intermolecular force. This is supported by (Figure 1.), in which Distilled Water contained the slowest rate of evaporation at 0.00686 degrees Celsius per second, therefore having the strongest intermolecular force because of its hydrogen bond. Pentane had the fastest rate of evaporation, as shown in (Figure 1.), at 0.349 degrees Celsius per second because it consisted of the weakest intermolecular force, a london dispersion bond. This evidence was not only supported through the experiment in which my group performed, but it was also supported by claims made by other groups who performed the same experiment. Overall, the molecular shape and the intermolecular bond type affects the rate of evaporation in liquids, causing each liquid to evaporate at its own specific