Similar Vectors Diffusion and Permeability Measurement Apparatus- Mass Spectrometer 14 2 7 Fuel Cell Apparatus- Humidified Oxidant 16 2 8 Breathing Protection 4 2 1 Conical Flask 31 3 17 Fuel Cell Apparatus- Pressurized Liquid Reactants 19 2 10 Titration Apparatus 23 3 12 Fuel Cell Apparatus- Pumped Liquid Reactants 24 3 13 Redox Titration Using Indicator 17 2 9 Redox Titration Apparatus of Ferrous Ions by Ceric Ions 14 2 7 Microphone 96 12 55 Potentiometric Titration Apparatus 11 2 5 Glass Fuel Cell Schematic 9 2 4