In the preface of Physical Chemistry: A Modern Introduction,
2nd ed., the author writes,
This text has been designed and written especially for use in
a one-year, two-course sequence in introductory physical
chemistry.... The text is organized in a way that minimizes
extraneous material unnecessary to understand the
fundamental concepts while focusing on a strong molecular
approach to the subject.
In fact, these intentions are reduced to a reorganization (or
disorganization) of concepts and equations that is difficult to
understand, and that does not advance the study of physical
chemistry.
The book begins with a nominal World of Atoms and
Molecules, a chapter that is not easy to assimilate because a
large proportion of pages are dedicated to defining and
studying the concept of configurations (which are only applied
10 chapters later). This subject could be put in an appendix,
because it is limited to a set of mathematical developments of
doubtful utility. Note that this solution has been applied to
other concepts of equal or lesser difficulty.
With that limited background, the book continues with the
study of gases, beginning with the ideal gas law (where eq 2.7 is
not deduced directly from eqs 2.1, 2.3, and 2.5, as the author
implies). The text mixes macroscopic and microscopic
behavior, with consequent problems for students. It is only in
Chapter 3 that the true physical chemistry really begins with the
study of thermodynamics. But again, it is not easy to separate
the fundamental concepts (which is the great problem when we
teach thermodynamics!) that are hidden after a confusing set of
partial derivatives and unnecessary equations. Chapter 4
describes equilibrium as an application of thermodynamic
concepts. Here the description is incomplete and almost
erroneous. For example, it is suggested (Figure 4.1) that the
plot of the phase diagram for water is a typical example, but it is
in fact an exception. The authors try to explain the slope
predicted by the Clapeyron equation by means of impossible
pairs of ΔH/ΔV values because in their framework ΔH can
never be negative (page 90 and Table 4.1). This chapter is not
easy to follow without a deep knowledge of equilibrium, which
it is doubtful that students have at this point of the book.
In Chapter 5, the study of solutions and chemical equilibrium
are mixed. The phase diagram of water is used again to explain
the lowering of the fusion point, and again it is not valid for all
systems. Kinetic chemistry is described next in Chapter 6,
before other equilibrium examples, and the chapter starts with a
triple micro−macro−microscopic feature that does not serve as
a description of the (critically important) processes that are
time-dependent. As part of this chapter, only electrochemical
reactions that are time-independent, such as the Nernst
equation, are studied, without any mention of other timedependent
processes (such as Butler−Volmer and Tafel
mechanisms), which are quite important examples of electrochemical
kinetics.
The study of the microscopic world begins with the
description of the classic vibrational behavior of particle
systems, before the introduction of quantum mechanics
postulates. Other chapters are dedicated to the machinery of
the quantum mechanics (avoiding examples such as the twodimensional
particle in the box system, which is useful to
explain the degeneration of states). Of the two important
systems, atoms and molecules, there are only two pages
devoted to molecules in a physical chemistry book of more than
400 pages. At this point vibrational−rotational spectroscopy is
explained, followed by a description of atomic and molecular
systems, and electronic spectroscopy. The relationship between
the macroscopic and microscopic world is treated in Chapter
11, which is titled Statistical Mechanics, but should be titled
statistical thermodynamics. The authors join the terms “state
variables” and “state functions” in one category. The final
chapters are dedicated to radiation−matter interaction
examples (magnetic resonance, but no X-ray or neutron
diffraction), and the chemistry of surfaces.
Throughout the text there are inconsistencies and errors that
should be revised: “Since ln C is dimensionless, then entropy
has units of energy per unit of temperature” (p 9) when
entropy, and consequently, its units, were defined by the
second law before introducing the Boltzmann equation; the
phase rule is defined in page 87 but it is already used in page
82; Appendix J is identical to Table F.2, and so forth.
It is certain that new, more pedagogical visions of physical
chemistry are needed. “Instead, students should see that
physical chemistry provides a coherent framework for chemical
knowledge, from the molecular level to the macroscopic level”,
the author writes in the preface. I agree with this statement, but
Physical Chemistry: A Modern Introduction, 2nd ed. has not
succeeded, and an important opportunity has been lost.
In the preface of Physical Chemistry: A Modern Introduction,
2nd ed., the author writes,
This text has been designed and written especially for use in
a one-year, two-course sequence in introductory physical
chemistry.... The text is organized in a way that minimizes
extraneous material unnecessary to understand the
fundamental concepts while focusing on a strong molecular
approach to the subject.
In fact, these intentions are reduced to a reorganization (or
disorganization) of concepts and equations that is difficult to
understand, and that does not advance the study of physical
chemistry.
The book begins with a nominal World of Atoms and
Molecules, a chapter that is not easy to assimilate because a
large proportion of pages are dedicated to defining and
studying the concept of configurations (which are only applied
10 chapters later). This subject could be put in an appendix,
because it is limited to a set of mathematical developments of
doubtful utility. Note that this solution has been applied to
other concepts of equal or lesser difficulty.
With that limited background, the book continues with the
study of gases, beginning with the ideal gas law (where eq 2.7 is
not deduced directly from eqs 2.1, 2.3, and 2.5, as the author
implies). The text mixes macroscopic and microscopic
behavior, with consequent problems for students. It is only in
Chapter 3 that the true physical chemistry really begins with the
study of thermodynamics. But again, it is not easy to separate
the fundamental concepts (which is the great problem when we
teach thermodynamics!) that are hidden after a confusing set of
partial derivatives and unnecessary equations. Chapter 4
describes equilibrium as an application of thermodynamic
concepts. Here the description is incomplete and almost
erroneous. For example, it is suggested (Figure 4.1) that the
plot of the phase diagram for water is a typical example, but it is
in fact an exception. The authors try to explain the slope
predicted by the Clapeyron equation by means of impossible
pairs of ΔH/ΔV values because in their framework ΔH can
never be negative (page 90 and Table 4.1). This chapter is not
easy to follow without a deep knowledge of equilibrium, which
it is doubtful that students have at this point of the book.
In Chapter 5, the study of solutions and chemical equilibrium
are mixed. The phase diagram of water is used again to explain
the lowering of the fusion point, and again it is not valid for all
systems. Kinetic chemistry is described next in Chapter 6,
before other equilibrium examples, and the chapter starts with a
triple micro−macro−microscopic feature that does not serve as
a description of the (critically important) processes that are
time-dependent. As part of this chapter, only electrochemical
reactions that are time-independent, such as the Nernst
equation, are studied, without any mention of other timedependent
processes (such as Butler−Volmer and Tafel
mechanisms), which are quite important examples of electrochemical
kinetics.
The study of the microscopic world begins with the
description of the classic vibrational behavior of particle
systems, before the introduction of quantum mechanics
postulates. Other chapters are dedicated to the machinery of
the quantum mechanics (avoiding examples such as the twodimensional
particle in the box system, which is useful to
explain the degeneration of states). Of the two important
systems, atoms and molecules, there are only two pages
devoted to molecules in a physical chemistry book of more than
400 pages. At this point vibrational−rotational spectroscopy is
explained, followed by a description of atomic and molecular
systems, and electronic spectroscopy. The relationship between
the macroscopic and microscopic world is treated in Chapter
11, which is titled Statistical Mechanics, but should be titled
statistical thermodynamics. The authors join the terms “state
variables” and “state functions” in one category. The final
chapters are dedicated to radiation−matter interaction
examples (magnetic resonance, but no X-ray or neutron
diffraction), and the chemistry of surfaces.
Throughout the text there are inconsistencies and errors that
should be revised: “Since ln C is dimensionless, then entropy
has units of energy per unit of temperature” (p 9) when
entropy, and consequently, its units, were defined by the
second law before introducing the Boltzmann equation; the
phase rule is defined in page 87 but it is already used in page
82; Appendix J is identical to Table F.2, and so forth.
It is certain that new, more pedagogical visions of physical
chemistry are needed. “Instead, students should see that
physical chemistry provides a coherent framework for chemical
knowledge, from the molecular level to the macroscopic level”,
the author writes in the preface. I agree with this statement, but
Physical Chemistry: A Modern Introduction, 2nd ed. has not
succeeded, and an important opportunity has been lost.
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