This isn’t seen in singular molecules and is only seen in two degrees in linear molecules because they rotate only in two degrees. For this reason, a diatomic molecule has only two degrees of freedom in the rotational sense. This gives the diatomic molecule like N2 or diatomic nitrogen a total of five degrees of freedom. The degrees of freedom corresponding to translations and rotations are called the rigid degrees of freedom, since they do not involve any deformation of the molecule. Vibrational degrees of freedom are not rigid with these degrees of freedom depending on the shape and characteristics of the molecule. Vibrational degrees involve deformations and changes between atoms of a molecule. An example is nitrous oxide or N2O, which is linear so it has two rotational degrees of freedom but 8 vibrational degrees of freedom. This leads to a total of 13 degrees of freedom (2 rotational, 3 translational, and 8 vibrational) and a greater heat capacity.
CALORIMETRY Calorimetry means “heat-measurement” in Latin and Greek, which basically means that this is the science of measuring the amount of heat in a substance. It can measure the amount of heat consumed (in an endothermic process), the amount of heat produced (in an exothermic process), or the amount of heat dissipated by a sample. Calorimetry can be used in a vast number of chemical and biological systems as it can be used whenever heat is exchanged, generated, or lost. A calorimeter is a device that measures the heat of a reaction. Reactants can be mixed in a calorimeter, allowed to react, and then there will be a measurement of the temperature difference before and after the reaction. A calorimeter does not have to be fancy or complex. It simply has to contain a reaction and measure temperatures. A calorimeter can be operated under constant pressure (such as atmospheric pressure) or constant volume. It can measure the heat capacity of the calorimeter itself by adding heat to it and measuring the amount of heat that is required to raise the temperature of the entire calorimeter by 1-degree Kelvin. This will be an extremely small number, requiring very sensitive thermometers.
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