A constant characterizing these substances equals the difference between two types of heat capacity, per Mayer’s relation. These substances do not change (-5[1])temperature while undergoing a Joule expansion. (-5[1])A fugacity (10[2])coefficient (10[1])of 1 (10[1])characterizes these substances, (10[4])which (-5[1])have a value of 0 for the “b” coefficient (10[1])measuring (10[1])excluded volume (10[3])in the van der Waals (10[1]-5[1])equation. (10[4])Avogadro’s number (10[3]-5[1])times the (10[1])Boltzmann (10[1])constant (10[1])equals (10[1])a constant named for these substances, (10[2])which are (10[1]-5[1])typically assumed (10[1])to have (10[2])no (10[1])intermolecular (10[2])forces. (10[3]-5[4])For 10 (10[1])points, (10[3])8.314 joules per mole-kelvin (10[1])is the value of a constant named for what (10[1])substances, (10[2])governed by the equation (10[1])“PV (10[1])equals nRT”? (10[2])■END■ (10[6]0[2])