[Donald A. McQuarrie, John D. Simon] Physical Chem(BookZZ.org)
1279 pág.

[Donald A. McQuarrie, John D. Simon] Physical Chem(BookZZ.org)


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e v e r y o n e o f t h e s e s o - c a l l e d r e v i e w s m a y a c t u a l l y b e a r e v i e w f o r 
y o u . E v e n i f s o m e o f t h e t o p i c s a r e n e w t o y o u ( o r s e e m t h a t w a y ) , w e d i s c u s s o n l y 
t h e m i n i m u m a m o u n t t h a t y o u n e e d t o k n o w t o u n d e r s t a n d t h e s u b s e q u e n t p h y s i c a l 
c h e m i s t r y . W e h a v e p o s i t i o n e d t h e s e r e v i e w s s o t h a t t h e y i m m e d i a t e l y p r e c e d e t h e f i r s t 
c h a p t e r t h a t u s e s t h e m . B y r e a d i n g t h e s e r e v i e w s f i r s t ( a n d d o i n g t h e p r o b l e m s ! ) , y o u 
w i l l b e a b l e t o s p e n d l e s s t i m e w o r r y i n g a b o u t t h e m a t h , a n d m o r e t i m e l e a r n i n g t h e 
p h y s i c a l c h e m i s t r y , w h i c h i s , a f t e r a l l , y o u r g o a l . 
T o t h e I n s t r u c t o r 
T h i s t e x t e m p h a s i z e s a m o l e c u l a r a p p r o a c h t o p h y s i c a l c h e m i s t r y . C o n s e q u e n t l y , u n l i k e 
m o s t o t h e r p h y s i c a l c h e m i s t r y b o o k s , w e d i s c u s s t h e p r i n c i p l e s o f q u a n t u m m e c h a n i c s 
f i r s t a n d t h e n u s e t h e s e i d e a s e x t e n s i v e l y i n o u r s u b s e q u e n t d e v e l o p m e n t o f t h e r m o d y -
n a m i c s a n d k i n e t i c s . F o r e x a m p l e , f r o m t h e C o n t e n t s y o u w i l l s e e t h a t c h a p t e r s t i t l e d 
T h e B o l t z m a n n F a c t o r a n d P a r t i t i o n F u n c t i o n s ( C h a p t e r 1 7 ) a n d P a r t i t i o n F u n c t i o n s 
a n d I d e a l G a s e s ( C h a p t e r 1 8 ) c o m e b e f o r e T h e F i r s t L a w o f T h e r m o d y n a m i c s ( C h a p -
t e r 1 9 ) . T h i s a p p r o a c h i s p e d a g o g i c a l l y s o u n d b e c a u s e w e t r e a t o n l y e n e r g y , p r e s s u r e , 
a n d h e a t c a p a c i t y ( a l l m e c h a n i c a l p r o p e r t i e s t h a t t h e s t u d e n t s h a v e d e a l t w i t h i n t h e i r 
g e n e r a l c h e m i s t r y a n d p h y s i c s c o u r s e s ) i n C h a p t e r s 1 7 a n d 1 8 . T h i s a p p r o a c h a l l o w s 
u s t o i m m e d i a t e l y g i v e a m o l e c u l a r i n t e r p r e t a t i o n t o t h e t h r e e l a w s o f t h e r m o d y n a m -
i c s a n d t o m a n y t h e r m o d y n a m i c r e l a t i o n s . T h e m o l e c u l a r i n t e r p r e t a t i o n o f e n t r o p y i s 
a n o b v i o u s e x a m p l e ( a n i n t r o d u c t i o n t o e n t r o p y w i t h o u t a m o l e c u l a r i n t e r p r e t a t i o n i s 
s t r i c t l y f o r p u r i s t s a n d n o t f o r t h e f a i n t o f h e a r t ) , b u t e v e n t h e c o n c e p t s o f w o r k a n d h e a t 
i n t h e F i r s t L a w o f T h e r m o d y n a m i c s h a v e a n i c e , p h y s i c a l , m o l e c u l a r i n t e r p r e t a t i o n i n 
t e r m s o f e n e r g y l e v e l s a n d t h e i r p o p u l a t i o n s . 
T e c h n o l o g i c a l a d v a n c e s d u r i n g t h e p a s t f e w d e c a d e s h a v e c h a n g e d t h e f o c u s o f 
p h y s i c a l c h e m i c a l r e s e a r c h a n d t h e r e f o r e s h o u l d a f f e c t t h e t o p i c s c o v e r e d i n a m o d e m 
p h y s i c a l c h e m i s t r y c o u r s e . V e r y f e w p h y s i c a l c h e m i s t s t o d a y m e a s u r e s u c h q u a n t i t i e s 
a s v a p o r p r e s s u r e s , m u l t i c o m p o n e n t p h a s e d i a g r a m s , e l e c t r o d e p o t e n t i a l s , o r t h e t h e r -
m o d y n a m i c p r o p e r t i e s o f i o n s i n s o l u t i o n . T o i n t r o d u c e t h e t y p e o f p h y s i c a l c h e m i c a l 
r e s e a r c h t h a t i s c u r r e n t l y b e i n g d o n e , w e h a v e i n c l u d e d c h a p t e r s s u c h a s C o m p u t a t i o n a l 
Q u a n t u m C h e m i s t r y ( C h a p t e r 1 1 ) , G r o u p T h e o r y ( C h a p t e r 1 2 ) , N u c l e a r M a g n e t i c R e s -
o n a n c e S p e c t r o s c o p y ( C h a p t e r 1 4 ) , L a s e r s , L a s e r S p e c t r o s c o p y , a n d P h o t o c h e m i s t r y 
( C h a p t e r 1 5 ) , a n d G a s - P h a s e R e a c t i o n D y n a m i c s ( C h a p t e r 2 8 ) . T h e i n c l u s i o n o f n e w 
t o p i c s n e c e s s i t a t e d t h e o m i s s i o n o f s o m e t o p i c s t h a t a r e t r a d i t i o n a l l y c o v e r e d i n a p h y s -
i c a l c h e m i s t r y c o u r s e . T h e c h o i c e o f w h a t t o p i c s t o d e l e t e w a s d i f f i c u l t , b u t w e h a d 
X I X 
XX PHYSICAL CHEMISTRY 
to make such decisions because our publisher was reluctant to publish a 2000 page 
physical chemistry book. 
For example, we have no chapters on the thermodynamics of solutions, which 
usually discuss Raoult's law and deviations from it, leading to the introduction of 
activities and their associated standard states. As important as this material might 
be, some topics must be eliminated to make room for new material. Furthermore, an 
informal survey we made over the past year or so has assured us that most instructors 
teaching physical chemistry for the first few times are not comfortable with Raoult's law 
standard states and Henry's law standard states, and they don't really enjoy teaching 
the thermodynamics of solutions. Another classical topic that we have eliminated 
is electrochemistry. This topic, which traditionally constitutes a chapter in physical 
chemistry books, is now amply covered in analytical chemistry courses. Some other 
traditional topics that have been omitted are the Gibbs phase rule, the Carnot cycle, 
Debye-Hiickel theory, and ternary or more complicated phase diagrams. Should a 
modern course in physical chemistry reflect material that increasingly few physical 
chemists use in their research and that many have not seen other than in the courses they 
took years ago? We think not. Although such information is undoubtedly important, 
especially in fields such as environmental chemistry and geological chemistry, these 
fields are growing to such an extent that specialized courses are being offered that 
address the essential physical chemical topics and their applications in much more 
detail than the necessarily cursory treatment they receive in a standard course in 
physical chemistry. 
Some instructors have raised the question about whether these omitted topics are 
on the GRE exam and whether their students would be disadvantaged. The answer to 
this question is "No." In fact, one of us was recently on the GRE Chemistry Board for 
eight years and was Chair for the last two of them. More than ten years ago, the exam 
was rather heavy in classical thermodynamics, but in the past decade, the committee 
made a serious effort to significantly de-emphasize the thermodynamics in favor of 
quantum chemistry and spectroscopy. The need for this book became clear as a result 
of the GRE Chemistry Board meetings. 
Keeping in mind that our purpose is to teach the next generation of chemists, 
the quantities, units, and symbols used in this text are those presented in the 1993 
International Union of Pure and Applied Chemistry (IUPAC) publication Quantities, 
Units, and Symbols in Physical Chemistry by Ian Mills et al. (Blackwell Scientific 
Publications, Oxford). Our decision to follow the IUPAC recommendations means 
that some of the symbols, units, and standard