Very quick question regarding melting point and purity

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SUMMARY

The melting point of 147ºC (dec.) indicates that the sample decomposed rather than melted, suggesting that the sample may contain reactive impurities. A pure sample should exhibit a clear melting point without decomposition. The presence of decomposition implies that the sample is not 100% pure, as reactive impurities such as strong mineral acids or oxidizers can cause this behavior. Therefore, no definitive conclusions about purity can be drawn without additional information on the expected melting behavior of the analyte.

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Chemistry students, analytical chemists, and professionals involved in purity testing and material characterization will benefit from this discussion.

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Homework Statement


For the following melting point, indicate what might be concluded regarding the sample purity:

Melting point: 147ºC (dec.)



Homework Equations


I assume that (dec.) means that the sample decomposed.


The Attempt at a Solution


I am wondering if this means that the sample is practically 100% pure because it decomposed in such a small temperature window, or if the fact that the sample decomposed means that no useful information can be obtained.
 
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I would say the latter unless you know something more about how a pure sample of the analyte should behave. If it is supposed to melt and it decomposes, you have a reactive impurity. In my experience, reactive impurities mean strong mineral acids or oxidizers.
 
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