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  2. Chemical stability - Wikipedia

    en.wikipedia.org/wiki/Chemical_stability

    This type of chemical thermodynamic equilibrium will persist indefinitely unless the system is changed. Chemical systems might undergo changes in the phase of matter or a set of chemical reactions. State A is said to be more thermodynamically stable than state B if the Gibbs free energy of the change from A to B is positive.

  3. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    All chemical transformations pass through an unstable structure called the transition state, which is poised between the chemical structures of the substrates and products. The transition states for chemical reactions are proposed to have lifetimes near 10 −13 seconds, on the order of the time of a single bond vibration. No physical or ...

  4. Hydrodynamic stability - Wikipedia

    en.wikipedia.org/wiki/Hydrodynamic_stability

    The study of hydrodynamic stability aims to find out if a given flow is stable or unstable, and if so, how these instabilities will cause the development of turbulence. [1] The foundations of hydrodynamic stability, both theoretical and experimental, were laid most notably by Helmholtz, Kelvin, Rayleigh and Reynolds during the nineteenth ...

  5. Valley of stability - Wikipedia

    en.wikipedia.org/wiki/Valley_of_stability

    A common example of an unstable nuclide is carbon-14 that decays by beta decay into nitrogen-14 with a half-life of about 5,730 years: 14 6 C → 14 7 N + e − + ν e. In this form of decay, the original element becomes a new chemical element in a process known as nuclear transmutation and a beta particle and an electron antineutrino are emitted.

  6. Metastability - Wikipedia

    en.wikipedia.org/wiki/Metastability

    the state of least energy is the only one the system will inhabit for an indefinite length of time, until more external energy is added to the system (unique "absolutely stable" state); the system will spontaneously leave any other state (of higher energy) to eventually return (after a sequence of transitions) to the least energetic state.

  7. Stable and unstable stratification - Wikipedia

    en.wikipedia.org/wiki/Stable_and_unstable...

    Stable stratification of fluids occurs when each layer is less dense than the one below it. Unstable stratification is when each layer is denser than the one below it. Buoyancy forces tend to preserve stable stratification; the higher layers float on the lower ones. In unstable stratification, on the other hand, buoyancy forces cause convection ...

  8. Chemical thermodynamics - Wikipedia

    en.wikipedia.org/wiki/Chemical_thermodynamics

    Breaking and making chemical bonds involves energy release or uptake, often as heat that may be either absorbed by or evolved from the chemical system. Energy released (or absorbed) because of a reaction between chemical substances ("reactants") is equal to the difference between the energy content of the products and the reactants.

  9. Bistability - Wikipedia

    en.wikipedia.org/wiki/Bistability

    In a conservative force field, bistability stems from the fact that the potential energy has two local minima, which are the stable equilibrium points. [2] These rest states need not have equal potential energy. By mathematical arguments, a local maximum, an unstable equilibrium point, must lie between the two minima. At rest, a particle will ...