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Melting Point

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Melting Point
Mixture Melting Points

Abstraction
Determining the melting point is very significant in order to identify an unknown. In this experiment, measuring the melting point was done by using melting point apparatus. The melting point of the unknown sample #10 was 111.5˚C. There were two possible compounds which were dibenzoyl ethylene and o-Toluic acid because their melting points were 111.2˚C and 109.8˚C when each compound was mixed with the unknown. Therefore, the unknown #10 was dibenzoyl ethylene.
Introduction
The melting point is defined as the temperature at which the solid is in equilibrium with its liquid, and this characteristic is very unique, so a substance can be determined by the melting point. Determination of the melting point is very important technique in many areas of chemistry especially, in organic chemistry area because the melting point is really significant in order to identify the purity and the identity of a substance. Measuring the melting point is a fast and cost-effective technique which remains a strong link to the vast pre-instrumental chemistry literature, so the technique is still used for measuring purity of organic and pharmaceutical compounds. For that reason, determination of the melting point is more than just a classroom exercise in the organic chemistry lab.
Objective/Purpose
In this experiment, the identity of the unknown will be determined by measuring the melting point of the unknown and comparing the melting points of possible mixtures.

Background
The melting point of a material is the temperature at which the changes of the state from a solid to a liquid state, and is very unique physical constant for all substances. The mixture melting point is useful in confirming the identity of an unknown by mixing with known compound whose melting point is known because the melting point of the mixture tends to be almost the same temperature as the melting point of the known if they are the same substances. In addition, purity

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