For the ideal gas equation PV=nRT to hold true, the gas must be an ideal gas, which consists of separate particles that behave as point masses. The particles should be far apart and not exert forces on each other, and they must undergo elastic collisions. The conditions of constant pressure, volume, and temperature are not required for the equation's validity, as these variables can change. The discussion emphasizes the importance of understanding the assumptions behind the ideal gas law. Overall, the ideal gas law applies under specific conditions that characterize ideal gas behavior.