12. 13. 14. The molar heat of vaporization of water is 42 kJ/mol. How much energy is released by the condensation of 3.0 g of water? a. 0.88 kJ b. 7.0 kJ c. 130 kJ d. 250 kJ e. 0.07 kJ When solid ammonium chloride, NH4Cl, is added to water, the temperature of the solution decreases. Which statement best describes this observation? a. The reaction is exothermic b. Heat is released from the system, so it feels cooler. C. NH4Cl(s) NH4Cl(aq) + 33.6 kJ d. NH4Cl(s) → NH4Cl(aq) AH = +33.6 kJ e. NH4Cl(s) + H₂O(1) → NH4Cl(aq) AS = - 33.6 kJ The presence of a catalyst is thought to increase the rate of a reaction by a. changing the products that are formed in the reaction b. decreasing the enthalpy change of the reaction c. increasing the enthalpy change of the reaction d. decreasing the activation energy of the reaction e. increasing the activation energy of the reaction

12. 13. 14. The molar heat of vaporization of water is 42 kJ/mol. How much energy is released by the condensation of 3.0 g of water? a. 0.88 kJ b. 7.0 kJ c. 130 kJ d. 250 kJ e. 0.07 kJ When solid ammonium chloride, NH4Cl, is added to water, the temperature of the solution decreases. Which statement best describes this observation? a. The reaction is exothermic b. Heat is released from the system, so it feels cooler. C. NH4Cl(s) NH4Cl(aq) + 33.6 kJ d. NH4Cl(s) → NH4Cl(aq) AH = +33.6 kJ e. NH4Cl(s) + H₂O(1) → NH4Cl(aq) AS = - 33.6 kJ The presence of a catalyst is thought to increase the rate of a reaction by a. changing the products that are formed in the reaction b. decreasing the enthalpy change of the reaction c. increasing the enthalpy change of the reaction d. decreasing the activation energy of the reaction e. increasing the activation energy of the reaction

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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