# efecto de la temperatura en el

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```Ilustraci&oacute;n 5.1. Calcular el avance de la descomposicion del tetr&oacute;xido de
nitr&oacute;geno puro, sobre intervalos de temperartura de 200 a 400&deg;K, a presione
de 0.1, 1 y 10 atm&oacute;sferas
N ⋅ O = 2NO
2
n := 2
ν :=
2
i := 1 .. n
&lt;-- numero de sustancias (Prod+React)
⎛ −1 ⎞
⎜
⎝ 2 ⎠ &lt;-- coeficientes estequiometricos
T&ordm; := 298.15⋅ &deg;K
∆H&ordm; :=
4
P&ordm; := 1 ⋅ atm
⎛ 2.23 ⎞ ⋅ kcal
⎜
⎝ 7.96 ⎠ mol
νT :=
∑ νi
j := 1 .. 4
νT = 1
i
&lt;-- temperatura y presion de referencia
K&ordm; := 0.154
δCp :=
⎛ 7.9 4.46⋅ 10− 2 −2.71⋅ 10− 5 0⋅ 10− 9 ⎞ cal
⎜
⋅
⎜
−2
−5
− 9 mol
−0.841 ⋅ 10
1.88⋅ 10 ⎠
⎝ 5.48 1.365 ⋅ 10
La Entalp&iacute;a de reacci&oacute;n se eval&uacute;a por:
∆Hrxn( T) :=
∑
i
ν i⋅ ∆H&ordm; i +
∑∑
j
ν i⋅
δCpi , j
j
(
j
⋅ T − T&ordm;
)
j
i
∆Hrxn ( T)
T
Aplicando la Ec. de van't Hoff
⎛⌠ T
⎞
⎜ ⎮ ∆Hrxn( T) d
K( T) := K&ordm; ⋅ exp ⎮
T
⎜
⎟
2
R⋅ T
⎜⎮
⌡
⎝ T&ordm;
⎠
T := 200 , 225 .. 400
log( K( T) )
T
Del balance de masa para esta reacci&oacute;n, podemos expresar para ε:
2
Kp =
∏
i= 1
y =
i
4⋅ ε
2
1−ε
2
⋅P
ε ( T , P) :=
y de all&iacute;:
K( T)
P⋅ ⎛⎜ 4 +
⎝
K( T) ⎞
P
⎠
⎛ 0.1 ⎞
calculando para varias presiones y temperaturas: P := ⎜ 1.0
⎜
⎝ 10 ⎠
T := 200 , 210 .. 400
ε ( T , P 1)
ε ( T , P 2)
ε ( T , P 3)
T
BIBLIOGRAFIA
Sandler, Stanley I. (1999). &quot;Chemical and Engineering Thermodynamics&quot;.
Third Edition. John Wiley &amp; Sons. New York.
Ing. Federico G. Salazar
```