Solubilities in the system comprising nitromethane and 2,2,4-trimethylpentane have been reported in two publications. Malesinska1 carried out measurements of the mutual solubilities of the components between 363 and 379 K by synthetic method. Rolla et al.2 studied mutual solubilities of (1) and (2) between 369 and 378 K by synthetic method. Values obtained by the graphical interpolation or extrapolation from the data sheets are presented in the following table. Data are "recommended" if two or more apparently reliable studies are in reasonable (± 5 % relative) agreement. All other data are regarded as tentative only.
The upper critical solution temperature has been reported as 377.8 K,2 378.20 K.1 Thus, the recommended value is: (378.0 ± 0.2) K.
The corresponding critical solution composition has been reported as xc1 = 0.665(Rolla et al.2) and xc1 = 0.670 (Malesinska1). The data average xc1 = 0.668 ± 0.003, (100 w1 = 51.8) this value is recommended. The numerical values reported in the above table have been approximated by the equation based on scaling law (described in the Introduction material to this volume "Relations of Solubility Data in Binary Systems Containing Nitromethane") and the following parameters have been adjusted:
a1 = 0.71810, a2 = 0.78552, b1 = 5.74595, b2 = -5.18987(mean standard error of estimate was 0.0029).
For approximation the recommended values of UCST and xc1 have been used. This relationship is presented in Fig. 15 together with experimental data reported by Malesinska1 and Rolla et al.2