DIAGRAMMES BINAIRES

DIAGRAMMES BINAIRES
Sommaire
!"#$%&'
()%$
*+
$,-'.+
(/,-!.+
01!#2
'$!2
32
$2
/#4
(*54
34
)!!&'4
)!!!&'
$,'.4
6(/!4
6!7
)$7
3!7
809
9
:%$9
(/$9
!
'&/$
8*#$
+
2613$
4;
7$
<;
0
$
:&=>
>

I. Éléments de thermochimie maths spé
A. Introduction de la notion d'enthalpie libre
!$/$-
!     ,3  
$$=$&$.?,3
.$"%$@!5
Q
-$
Q=dH
?$$
,&
P
.5
dH 
(3%5  %#    /$ 33$  !
-/,A!!B.
d S= Séchange  Scréation
Scréation=d S− Séchange 
,3C
d S systèmed S milieu extérieur
.
dS −Q
Tfrontière
,3&
T
!
T=Tmilieu extérieur
.
dS −Q
T
dS −dH
T
5
dH −T dS 
5
G=H−T S =UP V −T S
dGT , P
$,&
P
T
.
D$%$533
B. Évolution d'une même espèce chimique sous deux
>

phases à P et T constants
Aphase = Aphase 
moles 5n− n
!
E-!
d
A
phase 
&
phase 
-&
P
T
5
dGT , P = A , T , P , phase − A , T , P , phase d
35
dGT , P =−d
(   5  $ 
A
   (    A
B      $      
A
,      !  
#
A
.
 E
d
   $
dGT , P 
    /        
,!.
A
phase 
$!
phase 
$
 E
d
   $
dGT , P 
    /        
,!.
A
phase 
$!
phase 
$
 E
=
-/!?!&$
@
A ,T , P , phase = A ,T , P , phase 
P
-
T
#3&$,3%
$
K ° T
.
C. Expression du potentiel chimique
?5
=°TRT a
!
°T
$,
3.&
T
!
a
5  !            
P
,  33   .    
,%5#$&.
>

Cas étudié Activité
;3
a=P
P °
;3
i
;%
a=Pi
P ° =yi
P
P °
!5
Pi
5
yi
53
$
a=
,3.
$
i
      $
a=xi
xi
53
8>

II. Rappels changements d'états maths sup
A. Diagramme d'équilibre des phases (P,T)
Diagramme P , T pour l ' eau
B. Diagramme de Clapeyron (P,v)
*5--$-@-0-@F0-
3$--#$
+>
supercritique