ion transport number
英[ˈaɪən trænsˈpɔ:t ˈnʌmbə]美[ˈaɪən trænsˈpɔrt ˈnʌmbɚ]
Ion transport number is a quantity which indicates the different contribution of ions to the electric current in electrolytes due to different electrical mobility. It has been introduced by Johann Wilhelm Hittorf in 1853.