15. The solubility of lithium chloride (LiCI) in water is 74.5g / 100mL at 10 °C and 89.8 g / 100mL at 40 °C. What are the signs of enthalpy and entropy changes for lithium chloride dissolving? → LiCl(s) Li(aq) + Cl‍(aq) AH = AS = 16. If AHsolute = 30kJ/mol and AH solvent = 40 kJ/mol and AH mix = -90 kJ/mol, what is the value of AHsoln? D. Factors Affecting Solubility Solubility is influenced by the type of substance dissolving, the temperature, and the applied pressure of a gas when the gas is the solute. Example: Which dissolves better in water, CH3Cl or CH3NH2? Plan: The more alike the intermolecular forces between the substances, the more likely one will dissolve in another. We need to evaluate the types of intermolecular attractions present. Solution: CH3CI, CH3NH2, and water are all polar. CH3NH2 also can make hydrogen bonds, so it will most likely have a greater solubility in water than CHCI. 17. For each substance given in a-c below, choose which of the two substances it will dissolve in better and explain your reasoning: a. H2O in CH3CH2OH or CH3CH2CH2CH2CH2OH b. CaCl2 in H2O or CH3CH2OH

15. The solubility of lithium chloride (LiCI) in water is 74.5g / 100mL at 10 °C and 89.8 g / 100mL at 40 °C. What are the signs of enthalpy and entropy changes for lithium chloride dissolving? → LiCl(s) Li(aq) + Cl‍(aq) AH = AS = 16. If AHsolute = 30kJ/mol and AH solvent = 40 kJ/mol and AH mix = -90 kJ/mol, what is the value of AHsoln? D. Factors Affecting Solubility Solubility is influenced by the type of substance dissolving, the temperature, and the applied pressure of a gas when the gas is the solute. Example: Which dissolves better in water, CH3Cl or CH3NH2? Plan: The more alike the intermolecular forces between the substances, the more likely one will dissolve in another. We need to evaluate the types of intermolecular attractions present. Solution: CH3CI, CH3NH2, and water are all polar. CH3NH2 also can make hydrogen bonds, so it will most likely have a greater solubility in water than CHCI. 17. For each substance given in a-c below, choose which of the two substances it will dissolve in better and explain your reasoning: a. H2O in CH3CH2OH or CH3CH2CH2CH2CH2OH b. CaCl2 in H2O or CH3CH2OH

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 83QRT: Another step in the metabolism of glucose, which occurs after the formation of glucose6-phosphate,...

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