Final answer:
Standard Temperature and Pressure (STP) is a set of benchmark conditions for comparing properties of gases. It is defined as a temperature of 273 K (0°C) and a pressure of about 1 atm (0.986 atm).
Step-by-step explanation:
Standard Temperature and Pressure (STP) is a set of benchmark conditions used to compare other properties of gases. At STP, the temperature is 273 K (0°C) and the pressure is about 1 atm (0.986 atm). It is important to note that STP was historically defined with a standard pressure of 1 atm.