The measurements of the liquidliquid coexistence curve and the heat capacity for binary mixture {1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C(2)mim][NTf2]) + 1-propanol} have been precisely performed. The values of the critical exponents alpha and beta in the critical region were obtained and coincided well with the 3D-Ising ones. The complete scaling theory was applied to well represent the asymmetric behavior of the diameter of the coexistence curve, indicating an important role of the heat capacity related term in the complete scaling formulizm. A comparison of the reduced critical parameters to those predicted by the restricted primitive model clearly showed the solvophobic criticality of the studied system.