What is the value of the gas constant R in L atm / mol K?

The value of the gas constant R, which is commonly used in the ideal gas law equation PV = nRT, is 0.08206 L atm / mol K. This specific value is applicable when pressure is measured in atmospheres (atm), volume in liters (L), and temperature in Kelvin (K).

The ideal gas law relates the four variables of pressure (P), volume (V), number of moles (n), and temperature (T) through the gas constant R, which allows us to calculate one variable if the others are known.

Other constants like 8.314 J/(mol K) represent the gas constant in different units, specifically when dealing with energy; 6.022 is Avogadro's number, which relates to the number of molecules in a mole; and 1.987 cal/(mol K) is another expression of R in calorie units. Each of these values serves a specific context in physical chemistry, but for calculations involving pressure in atmospheres, volume in liters, and temperature in Kelvin, 0.08206 L atm / mol K is the correct and commonly used value.