Melting Points Lab Report

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Melting Points
Elizabeth McGrail
Organic Chemistry I
25 January 2013

ABSTRACT
The objectives of this lab are, as follows; to understand what occurs at the molecular level when a substance melts; to understand the primary purpose of melting point data; to demonstrate the technique for obtaining the melting point of an organic substance; and to explain the effect of impurities on the melting point of a substance. Through the experimentation of three substances, tetracosane, 1-tetradecanol and a mixture of the two, observations can be made in reference to melting point concerning polarity, molecular weight and purity of the substance. When comparing the two substances, it is evident that heavy molecule weight of tetracosane allowed it to withstand the increased heat as a solid for a longer duration. The melting point of the combined molecules was much lower than each in its pure form. The finding reinforces the idea of derivatives and their importance when identifying a substance based on melting point. The conclusions drawn from the data found in this lab will aid in the recognition of molecules based on the properties they illustrate.

INTRODUCTION
The objectives of this lab are, as follows; to understand what occurs at the molecular level when a substance melts; to understand the primary purpose of melting point data; to demonstrate the technique for obtaining the melting point of an organic substance; and to explain the effect of impurities on the melting point of a substance. In this unit of study, I have learned that the physical properties of a molecule are commonly relied upon for identification. More specifically, a chemical’s melting point is often the physical property of choice for identification. The melting point of a substance is defined as the temperature at which the solid and liquid phases of a substance are in equilibrium with one another and both present at the same time. A molecule’s melting point is directly related to



References: Fryhle, C. B., & Solomons, T.W.G. (2011). Organic Chemistry (10th Ed). Hoboken, NJ: John Wiley & Sons Inc.

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