CHAPTER 19: FIGURE 19A.2 PHYSICAL CHEMISTRY: THERMODYNAMICS, STRUCTURE, AND CHANGE 10E | PETER ATKINS | JULIO DE PAULA ©2014 W. H. FREEMAN AND COMPANY PHYSICAL CHEMISTRY: QUANTA, MATTER, AND CHANGE 2E| PETER ATKINS| JULIO DE PAULA | RONALD FRIEDMAN ©2014 W. H. FREEMAN D COMPANY

CHAPTER 19: FIGURE 19A.6 PHYSICAL CHEMISTRY: THERMODYNAMICS, STRUCTURE, AND CHANGE 10E | PETER ATKINS | JULIO DE PAULA ©2014 W. H. FREEMAN AND COMPANY PHYSICAL CHEMISTRY: QUANTA, MATTER, AND CHANGE 2E| PETER ATKINS| JULIO DE PAULA | RONALD FRIEDMAN ©2014 W. H. FREEMAN D COMPANY

Transport Properties in Liquids Situation in liquids is qualitatively different from a gas, a certain amount of energy is necessary just to move a molecule  activation energy Ea to escape the interaction with its neighbors (e.g. by breaking H-bonds). probability of a molecule having Ea (i.e. able to move) mobility of a particle inversely prop. to viscosity  of the liquid   viscosity of a liquid decreases with increasing T

Transport properties of electrolyte solutions Conductance G: the inverse of electrical resistance R of a solution where A = sample cross sectional area; l = sample length; e = electrical conductivity (do not confuse with compressibility or thermal conductivity) [Ge] = S (Siemens) = -1 = CV-1s-1 [e] = Sm-1 Molar conductivity m = e/c where c = molar concentration of electrolyte [m] = Sm2mol-1; typical values m  102 Sm2mol-1

Transport properties of electrolyte solutions Kohlrausch Law: Note: Kohlrausch law is empirical, works best at low concentrations and for strong electrolytes m0 is the limiting molar conductivity (i.e. m for c  0) m0 = ++ + -- (law of independent migration of ions) where +/- is the number of cations/anions per electrolyte unit, +/- is the limiting molar conductivity of the cations/anions