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A reaction calorimeter is a calorimeter that measures the amount of energy released (in exothermic reactions) or absorbed (in endothermic reactions) by a chemical reaction. It does this by measuring the total change in temperature of an exact amount of water in a vessel.
Calorimetry requires that a reference material that changes temperature have known definite thermal constitutive properties. The classical rule, recognized by Clausius and Kelvin, is that the pressure exerted by the calorimetric material is fully and rapidly determined solely by its temperature and volume; this rule is for changes that do not involve phase change, such as melting of ice.
A desorption experiment starts with a fully hydrated sample which is placed in the sample chamber (the top chamber in the figure). In the bottom chamber a salt solution is injected. During the desorption experiment the sample is being slowly dehydrated and the salt solution takes up the water evaporated from the sample.
Differential scanning calorimetry (DSC) is a thermoanalytical technique in which the difference in the amount of heat required to increase the temperature of a sample and reference is measured as a function of temperature. [1] Both the sample and reference are maintained at nearly the same temperature throughout the experiment.
In more recent calorimeter designs, the whole bomb, pressurized with excess pure oxygen (typically at 30 standard atmospheres (3,000 kPa)) and containing a weighed mass of a sample (typically 1–1.5 g) and a small fixed amount of water (to saturate the internal atmosphere, thus ensuring that all water produced is liquid, and removing the need ...
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Polymers represent another large area in which thermal analysis finds strong applications. Thermoplastic polymers are commonly found in everyday packaging and household items, but for the analysis of the raw materials, effects of the many additive used (including stabilisers and colours) and fine-tuning of the moulding or extrusion processing used can be achieved by using differential scanning ...
In chemical thermodynamics, isothermal titration calorimetry (ITC) is a physical technique used to determine the thermodynamic parameters of interactions in solution. [ 1 ] [ 2 ] It is most often used to study the binding of small molecules (such as medicinal compounds) to larger macromolecules ( proteins , DNA etc.) in a label-free environment.