standard temperature and pressure

In chemistry and other sciences, STP or standard temperature and pressure is a standard set of conditions for experimental measurements, to enable comparisons to be made between sets of data. Internationally, the current STP defined by the IUPAC (International Union of Pure and Applied Chemistry) is an absolute pressure of 100.00 kPa (1 bar) and a temperature of 273.15 K (0 °C). Other organizations have established a variety of alternative definitions for the standard reference conditions of temperature and pressure, such as the SATP amongst others.
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Compare with SATP and standard state .Used to describe a substance at standard pressure and a temperature of 0°C (273.15 K).