The equation PV=nRT is known as the ideal gas law, which describes the relationship between pressure (P), volume (V), temperature (T), and the number of moles of gas (n). In this equation, R is the ideal gas constant, which varies depending on the units used. This law helps predict how gases behave under different conditions, making it essential in fields like chemistry and physics. In the ideal gas law, pressure is measured in units like atmospheres or pascals, while volume is typically in liters. Temperature must be in Kelvin for the equation to work correctly. The ideal gas law assumes that gases behave ideally, meaning they follow this equation under most conditions, although real gases may deviate at high pressures or low temperatures.