Not to be confused with Standard sea-level conditions.
For the conditions used in thermodynamic evaluations, see Standard state.
Standard temperature and pressure (STP) or Standard conditions for temperature and pressure are various standard sets of conditions for experimental measurements used to allow comparisons to be made between different sets of data. The most used standards are those of the International Union of Pure and Applied Chemistry (IUPAC) and the National Institute of Standards and Technology (NIST), although these are not universally accepted. Other organizations have established a variety of other definitions.
In industry and commerce, the standard conditions for temperature and pressure are often necessary for expressing the volumes of gases and liquids and related quantities such as the rate of volumetric flow (the volumes of gases vary significantly with temperature and pressure): standard cubic meters per second (Sm3/s), and normal cubic meters per second (Nm3/s).
However, many technical publications (books, journals, advertisements for equipment and machinery) simply state "standard conditions" without specifying them; often substituting the term with older "normal conditions", or "NC". In special cases this can lead to confusion and errors. Good practice always incorporates the reference conditions of temperature and pressure. If not stated, some room environment conditions are supposed, close to 1 atm pressure, 293 K (20 °C), and 0% humidity.
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Standardtemperatureandpressure (STP) or Standard conditions for temperatureandpressure are various standard sets of conditions for experimental measurements...
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redefinition of the SI base units) at standardtemperatureandpressure (a temperature of 273.15 K and an absolute pressure of exactly 105 Pa). The ideal gas...
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occupancy, and at which laboratory experiments are usually performed. Standard conditions for temperatureandpressure ISO 1 – ISO standardtemperature, 20°C...
adiabatically brought to a standard reference pressure P 0 {\displaystyle P_{0}} , usually 1,000 hPa (1,000 mb). The potential temperature is denoted θ {\displaystyle...
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point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a...
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be the standardtemperatureandpressure. The standard molar entropy at pressure = P 0 {\displaystyle P^{0}} is usually given the symbol S°, and has units...
flowrate, the density of the gas should be used at Standardtemperatureandpressure. SCFM Standard cubic foot checalc.com Gas Volume Conversion onlineflow...
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astatine, or tennessine. All known hydrogen halides are gases at standardtemperatureandpressure. The hydrogen halides are diatomic molecules with no tendency...
organic chemical compound with chemical formula C 2H 6. At standardtemperatureandpressure, ethane is a colorless, odorless gas. Like many hydrocarbons...
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