Ammonium cation NH 4 dissociate in diluted aqueous solution according to the scheme: NH4+H20→→→→→→→→ NH3 + H30* At 25 °C ammonium cation has pKA = 9.245 and its standard dissociation enthalpy AH = 52.01 kJ mol¹¹. a) Is the dissociation of ammonium cation exothermic or endothermic? b) Consider, without calculation, if ammonia (NH3) is stronger or weaker base at higher temperature. c) Calculate PKA of the ammonium cation at 70 °C. d) Calculate AG and AS of dissociation at 25 °C.

Ammonium cation NH 4 dissociate in diluted aqueous solution according to the scheme: NH4+H20→→→→→→→→ NH3 + H30* At 25 °C ammonium cation has pKA = 9.245 and its standard dissociation enthalpy AH = 52.01 kJ mol¹¹. a) Is the dissociation of ammonium cation exothermic or endothermic? b) Consider, without calculation, if ammonia (NH3) is stronger or weaker base at higher temperature. c) Calculate PKA of the ammonium cation at 70 °C. d) Calculate AG and AS of dissociation at 25 °C.

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter16: Thermodynamics: Directionality Of Chemical Reactions

Section: Chapter Questions

Problem 91QRT: Actually, the carbon in CO2(g) is thermodynamically unstable with respect to the carbon in calcium...

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