Table 2: Experimental and calculated values for derivatives.

Sample 𝑇 𝑐 𝑃 𝑐 𝑉 𝑐 𝑟 𝑎 𝑉 c f ( 𝑑 𝑃 / 𝑑 𝑇 ) e x ( 𝑑 𝑃 / 𝑑 𝑇 ) 𝑇 𝛿

Ne44,4026,544,181,603,153,313,261,46
Ar150,8648,987,461,925,711,851,783,73
Kr209,3954,979,201,987,241,481,414,75
Xe289,7458,2811,942,189,331,131,093,37
H233,2313,166,391,445,641,871,87−0,06
N2126,2533,968,952,096,651,561,522,64
O2154,7750,877,342,005,321,921,891,58
F2144,0052,207,102,074,882,252,078,01
Cl2417,1777,0912,382,478,581,121,15−3,00
CH4190,5546,419,882,306,811,621,469,68
NH3405,60113,007,251,885,571,821,772,80
CO132,9434,989,362,166,821,501,481,23

𝑇 𝑐 (K), 𝑃 𝑐 *10−5 (Pa), and 𝑉 𝑐 *105 (m3/mole) are the critical temperature, pressure, and volume, respectively; 𝑟 𝑎 *1010 (m) is the atomic (molecular) radius; 𝑉 c f *105 (m3/mole) is the free critical volume; ( 𝑑 𝑃 / 𝑑 𝑇 ) e x *10−5 and ( 𝑑 𝑃 / 𝑑 𝑇 ) 𝑇 *10−5 (Pa/K) are the experimental and calculated derivatives, respectively; 𝛿 (%) is the relative error.