enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Solder alloys - Wikipedia

    en.wikipedia.org/wiki/Solder_alloys

    Soldering copper pipes using a propane torch and a lead-free solder. Solder is a metallic material that is used to connect metal workpieces. The choice of specific solder alloys depends on their melting point, chemical reactivity, mechanical properties, toxicity, and other properties. Hence a wide range of solder alloys exist, and only major ...

  3. Standard electrode potential (data page) - Wikipedia

    en.wikipedia.org/wiki/Standard_electrode...

    Variations from these ideal conditions affect measured voltage via the Nernst equation. Electrode potentials of successive elementary half-reactions cannot be directly added. However, the corresponding Gibbs free energy changes (∆G°) must satisfy ∆G° = – z FE°,

  4. Helmholtz free energy - Wikipedia

    en.wikipedia.org/wiki/Helmholtz_free_energy

    The Helmholtz free energy is defined as [3], where . F is the Helmholtz free energy (sometimes also called A, particularly in the field of chemistry) (SI: joules, CGS: ergs),; U is the internal energy of the system (SI: joules, CGS: ergs),

  5. Chemical potential - Wikipedia

    en.wikipedia.org/wiki/Chemical_potential

    When both temperature and pressure are held constant, and the number of particles is expressed in moles, the chemical potential is the partial molar Gibbs free energy. [1] [2] At chemical equilibrium or in phase equilibrium, the total sum of the product of chemical potentials and stoichiometric coefficients is zero, as the free energy is at a ...

  6. Free-energy relationship - Wikipedia

    en.wikipedia.org/wiki/Free-energy_relationship

    In physical organic chemistry, a free-energy relationship or Gibbs energy relation relates the logarithm of a reaction rate constant or equilibrium constant for one series of chemical reactions with the logarithm of the rate or equilibrium constant for a related series of reactions. [1]

  7. Electrochemical potential - Wikipedia

    en.wikipedia.org/wiki/Electrochemical_potential

    Electrochemical potential is important in biological processes that involve molecular diffusion across membranes, in electroanalytical chemistry, and industrial applications such as batteries and fuel cells. It represents one of the many interchangeable forms of potential energy through which energy may be conserved.

  8. Emission spectrum - Wikipedia

    en.wikipedia.org/wiki/Emission_spectrum

    The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation emitted due to electrons making a transition from a high energy state to a lower energy state. The photon energy of the emitted photons is equal to the energy difference between the two states. There are many possible ...

  9. Standard Gibbs free energy of formation - Wikipedia

    en.wikipedia.org/wiki/Standard_Gibbs_free_energy...

    The standard Gibbs free energy of formation (G f °) of a compound is the change of Gibbs free energy that accompanies the formation of 1 mole of a substance in its standard state from its constituent elements in their standard states (the most stable form of the element at 1 bar of pressure and the specified temperature, usually 298.15 K or 25 °C).