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 …show more content…
During the experiment, heating the water too quickly would create inaccurate data. If the water is heated too quickly, the thermometer may have a hard time keeping up with the temperate, thus displaying an inaccurate measurement. It would be must harder to obtain an accurate range, if this were the case, as the substance may melt faster than observable. A molecule’s melting point is reflective of its physical properties. Melting points disrupt intermolecular forces, spreading atoms over a greater surface area; melting points do not affect covalent bonds, thus are not chemical changes.
At the conclusion of this experiment, I have determined that the molecular weight of the given molecules played a greater role in determining its melting point. 1-tetradecanol, an alcohol, contains the functional group –OH. This type of bond is referred to as a Hydrogen bond; hydrogen bonds are much stronger than typical dipole-dipole bonds found in many ionic compounds. The molecular formula for tetracosane is C24H50. The molecule contains no functional group, so the intermolecular bonds are dispersion forces; the weakest bond noted between atoms. Given this information regarding polarity and the molecular weights of the compound, it is easy to conclude that the weight of the tetracosane caused it to have a higher melting point. CONCLUSION
At the conclusion of