What units does the ideal gas constant (R) use in the ideal gas law?

The ideal gas constant (R) is a fundamental constant used in the ideal gas law, expressed as PV = nRT, where P is pressure, V is volume, n is the number of moles of gas, R is the ideal gas constant, and T is temperature. The units of R vary depending on the units used for pressure, volume, and temperature.

In this context, all variables must be in a consistent set of units. The ideal gas law can be expressed in the SI unit system, which assumes pressure in Pascals (Pa), volume in cubic meters (m³), temperature in Kelvin (K), and the amount of substance in moles (mol). When R is defined in SI units, it is 8.314 J/(mol·K), where J (joules) is equivalent to kg·m²/s², reinforcing that the equation is adhering to SI standards.

This choice correctly recognizes that the ideal gas law contains variables that can all align under SI units. Other options suggest particular unit combinations that either limit the unit scope or incorrectly associate other measurement systems, demonstrating a lesser understanding of the broad applicability of R in different unit contexts.