DEP (C7H13N) 1-Diethylamino-2-propyne CAS No. 4079-68-9 Appearance: Clear colorless or yellowish liquid Assay: â?¥98% Density g/cm3 (20): 0.75~0.85 PH: â?¥7 Refractive Index(20):1.4245~1.4467 Application Leveling agent, brightener. for nickel plating