Evaporation Of Intermolecular Forces

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The purpose of this experiment was to investigate the relationship of dispersion forces as well as the hydrogen bonding forces in intermolecular attractions. In order to determine this, there were temperature probes that were covered in filter paper and placed in several liquids. When removed showed evaporation ; evaporation is the process when a solution in liquid state becomes a gaseous. It is also an endothermic process which results in the decrease of temperature. Evaporating molecules carry away the thermal energy when they leave the liquid. The determination of the amount of temperature decrease is based on the strength of the intermolecular forces of attraction. Intermolecular forces are forces that hold molecules together at different strengths depending on the force itself. The strength of intermolecular forces is related to the rate of evaporation, if the evaporation rate is higher, intermolecular forces are weaker. If the rate of evaporation is slower, the intermolecular forces are stronger. Alkanes and alcohols are two types of organic compounds in this experiment. The alkanes are pentane and hexane. Aside from carbon and hydrogen atoms, alcohol also contains the -OH function group. The alcohols that were used in this experiment were methanol and ethanol. There are two intermolecular forces, hydrogen bonding and dispersion forces which its relative strength is being determined by intermolecular forces. Hydrogen bonding can occur in one molecule, the hydrogen atom is bonded directly to a N, O or F atom which is the donor. That hydrogen is attracted to a lone pair on a N, O, or F atom which is in another molecule which is the acceptor. Both have to be there in order for the hydrogen bond to be able to occur. Dispersion forces are in between any two molecules and generally increase as the molecular weight of the molecule increases. It was hypothesized that
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