Editing Differential scanning calorimetry (section)

==Detection of phase transitions==
The basic principle underlying this technique is that when the sample undergoes a physical transformation such as [[phase transition]]s, more or less heat will need to flow to it than the reference to maintain both at the same temperature. Whether less or more heat must flow to the sample depends on whether the process is [[exothermic reaction|exothermic]] or [[endothermic reaction|endothermic]].

For example, as a solid sample [[melting|melts]] to a liquid, it will require more heat flowing to the sample to increase its temperature at the same rate as the reference. This is due to the absorption of heat by the sample as it undergoes the endothermic [[phase transition]] from solid to liquid. Likewise, as the sample undergoes exothermic processes (such as [[crystallization]]) less heat is required to raise the sample temperature. By observing the difference in heat flow between the sample and reference, differential scanning [[calorimeter]]s are able to measure the amount of heat absorbed or released during such transitions. DSC may also be used to observe more subtle physical changes, such as [[glass transition]]s. It is widely used in industrial settings as a quality control instrument due to its applicability in evaluating sample purity and for studying polymer curing.<ref name="Dean">{{cite book| vauthors = Dean JA |title=The Analytical Chemistry Handbook|place=New York|publisher=McGraw Hill, Inc.|year=1995|pages=15.1–15.5|isbn=0-07-016197-6}}</ref><ref name="Pugnor">{{cite book| vauthors = Pungor E |title=A Practical Guide to Instrumental Analysis|publisher=Boca Raton|place=Florida|year=1995|pages=181–191}}</ref><ref name="Skoog">{{cite book| vauthors = Skoog DA, Holler FJ, Nieman T |title=Principles of Instrumental Analysis |edition=5th |place=New York |year=1998 |pages=805–808 |isbn=0-03-002078-6}}</ref>