L4
.pdf. . 1, 4
4
, , -
, , -
.
– ( U H -
); – ( U H -
). : , – -
.
. .
, ( )
) ,
.
:
-( );
-;
-.
,
( ). -
, -
.
:
, , ».
-
( .3.2).
. , -
.
,
1 = 2 + 3 |
(3.34) |
. -
. – . -
.
1
www.fptl.ru
. . 1, 4
. . -
– :
|
pV = nRT |
(3.35) |
|
H1 |
|
|
|
|
|
|
|
|
|
|
|
|
|
2 |
3 |
|
:
p V = nRT |
(3.36) |
,
H = U + nRT |
(3.37) |
, n =0,
,
. , , ,
, -
.
, ,
n .
( n) -
, . n = .
,
.
2
www.fptl.ru
. . 1, 4
2H2 ( )+ O2 ) = 2H2O ( ) |
(3.38) |
298 , -
: – 248.2 .
.
n = = - = 0 – 3 = -3.
H = U + nRT = – 248.2 + (-3) 8.314 10-3 298 = - 291.6 .
. -
.
, -
. , ,
. , -
.
- , ,
1 (1,013 105 ).
– ,
, , 1.
–
1 (1,013 105 ).
.
25 (298 ). , , -
25 (298 ).
-
,
«0»,
H0r.
-
.
( ) -
1 ( ) -
.
H0f, 298. -
, 298 .
( )
.
3
www.fptl.ru
. . 1, 4
, .
( )
1
( 1.013 10-5 , ).
.
H0 , 298
, -
. -
, ; –
.
:
-
, -
.
H0r = i H0fi ( ) - i H0fi ( ) |
(4.1) |
:
-
, -
.
H0r = i H0 i ( ) - i H0 i ) |
(4.2) |
. -
( ), -
, .
, ,
. , -
CuSO4 5H2O.
4
www.fptl.ru
. . 1, 4
, ,
1 -
.
:
CuSO4 + 5H2O.= CuSO4 5H2O |
(4.3) |
-
. ,
. , -
CuSO4. Cu2+ SO42- -
. – ; – -
( .4.1).
Hr1
uSO4 Cu2+, SO42-
Hr2 |
Hr3 |
|
CuSO45H2O
.4.1. Cu2+ SO42- CuSO4.
, :
Hr1 = H 2 + H 3 |
(4.4) |
Hr1 – ( -
1
: , ).
Hr1 H 2 -
. , (4.4), -
.
-
.
, ,
, , -
5
www.fptl.ru
. . 1, 4
. ,
.
.
-
:
CH4 ) + CO2 ) = 2CO( ) + 2H2 ( )
H0fi ( H4) = - 74.85 ; H0fi ( ) = - 110.5 ; H0f ( 2) = 0,
H0 ( 2) = 0.
.
H0r = i H0fi ( ) - i H0fi ( )
2.
, 1 2.+ 2 = 2
. , -
.
H0r = i H0 i ( ) - i H0 i ( )
: H0 i ( ) = - 393.51 . :
H0f(CO2) = H0 i (C) - H0 i (CO2) = - 393.51 .
, , :
H0r = i H0fi ( ) - i H0fi ( ) = 2 (-110.5) + 0 – (-74.85) -393.51 = 247.39
. ( , )
. .
2.
1 , -
1 2.
. :
6
www.fptl.ru
. . 1, 4
1A1+ 2A2 = 3A3 + 4A4 |
(4.5) |
i i – , .
Hr = i Hi ( ) - i Hi ( ) |
(4.6) |
H |
r |
|
i |
H |
i |
|
( ) i |
H |
i |
|
( ).....(4.7) |
|||
|
|
|
|
|
|
|
|
|
||||||
T |
|
T |
|
T |
|
|||||||||
|
|
p |
|
|
|
p |
|
|
|
p |
|
, (4.7),
, ,
, -
. :
, -
.
H |
r |
|
i ci p ( ) i ci p ( ). C p ....(4.8) |
|
|
|
|
||
T |
|
|||
|
|
p |
|
,
, ,
U
r i c V ( ) i c V ( ) CV .....(4.9)
T V
(4.8) (4.9) . -
-
, .
.
, .
.
,
; , -
( . .4.2).
7
www.fptl.ru
. . 1, 4
-
.
-
.
Hr = Hr = cp T = Hr298 + cpdT (4.10) 298
Hr
C>0
C=0
C<0
T
.4.2.
, -
.
.
1., , .
Hr = Hr,298 + cp,298(T-298) (4.11)
2. cp .
, -
cp = a + b T + c T2 (4.12)
a = i ai ( ) - i ai ( ) |
(4.13) |
8
www.fptl.ru
. . 1, 4
b = i bi ( ) - i bi ( ) |
(4.14) |
. .
HT = Hr,298 + a(T-298)+( b/2)(T2-2982) + …..(4.15)
3., (4.10) -
Hf,T1:
HT = Hr,298 + a(T1-298)+ ( b/2)(T21-2982) + …+ Hf,T1 ++ a(T-T1)+ +( b/2)(T2-T21) +… (4.16)
. :
.
( ).
9
www.fptl.ru