What is the value of the gas constant (R) in atm?

The gas constant (R) is a fundamental constant in chemistry that relates pressure, volume, temperature, and the amount of substance in the ideal gas equation: PV = nRT. The most commonly used value of R in the context of pressure measured in atmospheres (atm) is 0.0821 L atm / K mol.

This specific value is derived based on the liter, atmosphere, Kelvin, and mole units being utilized in calculations related to gases. Each unit within the gas constant aligns to support calculations involving the ideal gas law, providing a consistent relation that allows chemists to predict the behavior of gases under various conditions.

While the other values are close, they do not represent the standard gas constant used when pressure is expressed in atmospheres. Hence, the selection of 0.0821 L atm / K mol is correct as it is the established value used in calculations with these units in the context of the ideal gas law.