**Thermodynamics and Chemical Reactions: Practice Questions****7. Heat Transfer and Work Done on a System**When heat is taken in by a system and work is done on the system by its surroundings, the internal energy of the system:- (a) will always increase- (b) will always decrease- (c) will increase if the heat \(>\) work- (d) will increase if heat \(<\) work- (e) will remain the same**8. Enthalpy Change in Chemical Reactions**If \(\Delta H\) for the reaction \(2A + B \rightarrow C + D\) is \(-100 \text{kJ}\), what is \(\Delta H\) in \(\text{kJ}\) for the reaction \(2C + 2D \rightarrow 4A + 2B\)?- (a) \(-50\)- (b) \(200\)- (c) \(-200\)- (d) \(100\)- (e) \(50\)**Explanation:***For Question 7:*- This question evaluates the understanding of the First Law of Thermodynamics, which states that the change in internal energy of a system (\(\Delta U\)) is equal to the heat added to the system (\(q\)) plus the work done on the system (\(w\)).*For Question 8:*- The problem involves calculating the enthalpy change (\(\Delta H\)) for a reverse reaction based on a given \(\Delta H\) for the original reaction. This tests knowledge of the principles of enthalpy change and Hess's law.These questions are essential for grasping fundamental concepts in thermodynamics and chemical kinetics, which are critical in fields such as chemistry and physics. Note: For an educational website, additional context or further explanation about the laws of thermodynamics and how to calculate enthalpy changes using given values might be beneficial.

The change in internal energy (ΔU) is given by ΔU = q + w where q = heat energy w = work done

7.Heat is taken in by a system and work is done on the system by its surroundings. The internal energy of the system (a) will always increase (b) will always decrease (c) will increase if the heat > work (d) will increase if heat < work (e) will remain the same. 8. If AH for the reaction 2A +B C+D is -100KJ, what is AH in kJ for the reaction 2C + 2D → 4A + 2B? (a) -50 (b) 200 (c) -200 (d) 100 (e) 50

7.Heat is taken in by a system and work is done on the system by its surroundings. The internal energy of the system (a) will always increase (b) will always decrease (c) will increase if the heat > work (d) will increase if heat < work (e) will remain the same. 8. If AH for the reaction 2A +B C+D is -100KJ, what is AH in kJ for the reaction 2C + 2D → 4A + 2B? (a) -50 (b) 200 (c) -200 (d) 100 (e) 50

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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