Atmospheric aerosols have received increasing attention within the past few years as their role in global climate change is investigated. However, it remains difficult to capture and quantify nucleation events at ambient concentrations in a smog chamber setting. A novel method was developed to mix two dilute reactants at near-ambient concentrations. This method was tested using at the UNC 270m^3 Outdoor Aerosol Chamber in Pittsboro, NC with a dark α-pinene/ozone system at near-ambient concentrations. These results were compared against the UNC Particle Mechanism and scientific literature to test the validity of the method. Further experiments were conducted to examine the role water vapor and background ammonium sulfate seed have in aiding or inhibiting nucleation events.