CHM 2045C  Module Seven Sample Exam Answers

Module Seven: Thermochemistry & States of Matter (Chapter 6)

A. ____(05) Laws of Thermodynamics & Related Terms-Section 6.1,19.3,19.4 Answer

B. ____(05) Discussion Questions-Chapter 6.4 Answer

C. ____(05) Specific Heat Problem-Section 6.2 Sample 2

D. ____(05) Enthalpy Change with Phase Change Prob-Sect 6.3 Answer Sample 2

E. ____(05) Enthalpy Change in Chemical Reaction-Section 6.4

F. ____ (05) Bomb Calorimeter Section 6.6 Answer

G. ____(10) Hess Law /Heats of Reaction Problem-Section 6.5, 6.7 Answer

H. ____(10) Standard Enthalpies of Formation Problem-Section 6.8 Answer

I.   ____(10) Bond Making/Breaking Problem-Section 9.8 Answer

K. ____(10) Key Terms-Chapter 6 Answer

L.  ____(15) Multiple Choice-Chapter 6 Old Final

______(85) Total = ______%

Module Six: Part A First Law of Thermodynamics & Related Terms   4 points

State the first law of thermodynamics:

The energy of the universe is a constant. [Law of Conservation of Energy-Energy can neither be created or destroyed, but can be converted from form to form]

Explain a Thermodynamic System and Its Surroundings

A thermodynamic system is defined as the object, or collection of objects, being studied.

The surroundings include everything outside the system that exchange energy with the system.

Define endothermic and exothermic processes.

In the exothermic process heat is transferred from a system to the surroundings.

An endothermic process is the opposite of an exothermic process: heat is transferred from surroundings of the system.

State the second law of thermodynamics (page 906):

In a spontaneous process, the entropy of the universe increases [Heat Death Theory of the Universe: all forms of energy can be transformed to heat, but not all heat energy can be transformed into other forms of energy-The heat content of the Universe is increasing.]

State the third law of thermodynamics (page 612):

There is no disorder (entropy) in a perfect crystal at 0 K, that is S=0.