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In chemistry, chemical stability is the thermodynamic stability of a chemical system, in particular a chemical compound or a polymer. [ 1 ] Chemical stability may also refer to the shelf-life of a particular chemical compound; that is the duration of time before it begins to degrade in response to environmental factors.
The kinetic and thermodynamic deprotonation of 2-methylcyclohexanone. If a much weaker base is used, the deprotonation will be incomplete, and there will be an equilibrium between reactants and products. Thermodynamic control is obtained, however the reaction remains incomplete unless the product enolate is trapped, as in the example below.
Triplet oxygen, 3 O 2, refers to the S = 1 electronic ground state of molecular oxygen (dioxygen). Molecules of triplet oxygen contain two unpaired electrons, making triplet oxygen an unusual example of a stable and commonly encountered diradical : [ 2 ] it is more stable as a triplet than a singlet .
Chemical thermodynamics involves not only laboratory measurements of various thermodynamic properties, but also the application of mathematical methods to the study of chemical questions and the spontaneity of processes. The structure of chemical thermodynamics is based on the first two laws of thermodynamics. Starting from the first and second ...
where is the dissociation energy at absolute zero, k B is the Boltzmann constant, h is the Planck constant, T is thermodynamic temperature, is vibrational frequency of the bond. This expression is very important since it is the first time that the factor k B T / h , which is a critical component of TST, has appeared in a rate equation.
Metastability is common in physics and chemistry – from an atom (many-body assembly) to statistical ensembles of molecules (viscous fluids, amorphous solids, liquid crystals, minerals, etc.) at molecular levels or as a whole (see Metastable states of matter and grain piles below). The abundance of states is more prevalent as the systems grow ...
A thermodynamic system consisting of a single phase in the absence of external forces, in its own internal thermodynamic equilibrium, is homogeneous. [41] This means that the material in any small volume element of the system can be interchanged with the material of any other geometrically congruent volume element of the system, and the effect ...
The chemical potential μ i of species i (atomic, molecular or nuclear) is defined, as all intensive quantities are, by the phenomenological fundamental equation of thermodynamics. This holds for both reversible and irreversible infinitesimal processes: [8]