The surface activity of the mixed surfactants C 1 2 H 2 5 (OC 2 H 4 ) 7 SO 4 Na-C 1 2 H 2 5 N (C 2 H 4 OH) 3 Cl (C 1 2 E 7 S-C 1 2 NEt 3 ) and C 8 H 1 7 C 6 H 4 (OC 2 H 4 ) 1 0 SO 4 Na (C 8 ΦE 1 0 S)-C 1 2 NEt 3 is much higher than those of C 1 2 E 7 S, C 1 2 NEt 3 and C 8 ΦE 1 0 S, respectively. With the mixing ratio approaching 1:1, the solubilization of hexanol by aqueous solutions of C 1 2 E 7 S-C 1 2 NEt 3 or C 1 2 NEt 3 -C 8 ΦE 1 0 S decreases, giving a V-shaped curve. The solubilization of polar compounds is directly proportional to the square of the amount of micellar charge. With the mixing ratio approaching 1:1, the solubilization of hexane increases, giving shaped curve. The viscosity of aqueous solutions of C 1 2 E 7 S-C 1 2 NEt 3 or C 8 ΦE 1 0 S-C 1 2 NEt 3 increases with a mixing ratio approaching 1:1, giving an inverted-V-shaped curve.