enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Standard temperature and pressure - Wikipedia

    en.wikipedia.org/wiki/Standard_temperature_and...

    Until 1982, STP was defined as a temperature of 273.15 K (0 °C, 32 °F) and an absolute pressure of exactly 1 atm (101.325 kPa). Since 1982, STP has been defined as a temperature of 273.15 K (0 °C, 32 °F) and an absolute pressure of exactly 1 bar (100 kPa, 10 5 Pa).

  3. Standard state - Wikipedia

    en.wikipedia.org/wiki/Standard_state

    The standard state of a material (pure substance, mixture or solution) is a reference point used to calculate its properties under different conditions.A degree sign (°) or a superscript Plimsoll symbol (⦵) is used to designate a thermodynamic quantity in the standard state, such as change in enthalpy (ΔH°), change in entropy (ΔS°), or change in Gibbs free energy (ΔG°).

  4. 2,5-Dimethoxy-4-methylamphetamine - Wikipedia

    en.wikipedia.org/wiki/2,5-Dimethoxy-4-methyl...

    STP was first synthesized and tested in 1963 by Alexander Shulgin, who was investigating the effect of 4-position substitutions on psychedelic amphetamines. [ 1 ] [ 5 ] In mid-1967, tablets containing 20 mg (later 10 mg) of STP were widely distributed in the Haight-Ashbury District of San Francisco under the name of STP, having been ...

  5. List of unsolved problems in chemistry - Wikipedia

    en.wikipedia.org/wiki/List_of_unsolved_problems...

    Download as PDF; Printable version ... This article needs attention from an expert in chemistry. ... "First 25 of 125 big questions that face scientific inquiry over ...

  6. Gay-Lussac's law - Wikipedia

    en.wikipedia.org/wiki/Gay-Lussac's_law

    Under STP, a reaction between three cubic meters of hydrogen gas and one cubic meter of nitrogen gas will produce about two cubic meters of ammonia.. The law of combining volumes states that when gases chemically react together, they do so in amounts by volume which bear small whole-number ratios (the volumes calculated at the same temperature and pressure).

  7. Enthalpy of sublimation - Wikipedia

    en.wikipedia.org/wiki/Enthalpy_of_sublimation

    In thermodynamics, the enthalpy of sublimation, or heat of sublimation, is the heat required to sublimate (change from solid to gas) one mole of a substance at a given combination of temperature and pressure, usually standard temperature and pressure (STP). It is equal to the cohesive energy of the solid.

  8. Sodium triphosphate - Wikipedia

    en.wikipedia.org/wiki/Sodium_triphosphate

    Sodium triphosphate (STP), also sodium tripolyphosphate (STPP), or tripolyphosphate (TPP), [1]) is an inorganic compound with formula Na 5 P 3 O 10. It is the sodium salt of the polyphosphate penta-anion, which is the conjugate base of triphosphoric acid. It is produced on a large scale as a component of many domestic and industrial products ...

  9. Vapor pressures of the elements (data page) - Wikipedia

    en.wikipedia.org/wiki/Vapor_pressures_of_the...

    David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition, online version. CRC Press. Boca Raton, Florida, 2003; Section 4, Properties of the Elements and Inorganic Compounds; Vapor Pressure of the Metallic Elements The equations reproduce the observed pressures to an accuracy of ±5% or better.