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สสสสสสสสสสสส สสสสสสสสสสสสสสสสสสสสสสสส สสสสสสสสสสสสสสสสสสสส สสสสสสส ส 40123 สสสส 3 จจจจจจจจจจจจจ (Chemical kinetics) สสสสสสสสสสสสสสสสสสสสส สสสสสสสสสสส สสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสส สสส สสสส สสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสส สสสสสสสสสสสสสสสสสสสสสสสสสสส สสสสสสสสสสสสส สสสสสสสสสสสสสสสสสสสสสสสสสสส สสสสสสสสสสสสสสส สสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสส สสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสส สสส สสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสส สสสสสสสสสสสสสส สสสส สสสสสสสสสสสสสสสสสสสสสสส สสส(II)สสสสสสสส(PbI 2 ) สสสสสสสสสสสสสสสสสสส สสสสสสสสสสส(II)สสสสสส(Pb(NO 3 ) 2 ) สสสสสสสสสสส สสสสสสสสสสสสสสสสสส(KI) สสสสสสสสสสสสสสสสสสสสส สสสสสสสสสสสสสสสสสสสสสสสสสสสส จจจจจจจจจจจจ จจจจจจจจจ(reaction rate : r) สสสสสสสสสสส สสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสสส สสสสสสสสสสสสสสสสสสส จจจจจจจจจจจจจ(Chemical kinetics) .สสสสส สสสสสสสสส 69

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(Chemical kinetics)

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40123 3

(Chemical kinetics)

(II)(PbI2) (II)(Pb(NO3)2) (KI) (reaction rate : r) (Chemical kinetics)

(Reactant) (Product)

1 A B1.

(g) (kg)

(L) (dm3)(cm3)

mol/dm3

(s) (min) (hr)

mol/dm3.s mol/s

A B C D

A + B

C + D

r

(

[ ] (mol/dm3) mol

t

+ -

1 mol/s

N2(g) + 3H2(g)

2NH3(g)

aA + bB

cC + dD

a, b, c d A, B, C D

2.

2.1 (Average rate)

2.2 (Instantaneous rate)

(slope) 100s 600s, 200s 500s, 350 350s = ([NO2] / (t

3.

(Rate law) Law of mass action

aA + bB

cC + dD

(1.1) Law of mass action

r ( [A]x[B]y

r = k[A]x[B]yr

k (Rate constant) k Specific rate constant

[A] A

[B] B

x, y A B r = k[A]x[B]y (Rate equation)

(Order of reaction) (x, y) x y (Overall order) 4.

(1.1) r = k[A][B]0 x = 1 y = 0 A B 1 (x + y = 0) A A 2 2 B B r = k[A]

r = k[A][B]2 x = 1 y = 2 3 ( x + y = 3) A A 2 2 B B 2 4 1

2HI H2 + I2r = k[HI]0 = k

2N2O 2N2 + O2r = k[N2O]

CH3CHO CH4 + COr = k[CH3CHO]2

2NO + 2H2 N2 + 2H2Or = k[NO]2[H2]

2NO + Br2 2NOBrr = k[NO]2[Br]

: , 1 , 2548 : 275

1 ()5.

1 2NO(g) + O2(g) 2NO2(g) 25 (C (mol/dm3) NO2(mol/dm3.s)

NOO2

1

2

3

40.01

0.01

0.01

0.020.01

0.02

0.03

0.030.007

0.014

0.021

0.084

1. x, y k2. 3. NO2 NO = 0.04 mol/dm3 O2 = 0.015 mol/dm3

r = k[NO]x[O2]y

.( 1 )

3 ( 1 )

0.021 = k[0.01]x[0.03]y

.( 2 )

4 ( 1 )

0.084 = k[0.02]x[0.03]y

.( 3 )

4 = 2x

22 = 2x

x = 2

1 ( 1 )

0.007 =k[0.01]x[0.01]y

.( 4 )

2 ( 1 )

0.014 =k[0.01]x[0.02]y

.( 5 )

2 =2y

y =1 10.007 =k[0.01]2[0.01]

k =(0.007) / (0.01)3= 7.0 x 103 dm6 mol-2 s-11.x = 2, y = 1, k = 7.0 x 103 dm6 mol-2 s-12. r = k[NO]2[O2]3. r = (7.0 x 103)(0.04)2(0.015)

=0.168mol dm-3 s-1

NO2 = 0.168mol dm-3 s-16.

2 (Collision theory) (Activated complex theory) 6.1 (Collision theory) (Activation energy : Ea)

(a) (b) (c) (d)

4 A B 6.2 (Activated complex theory) (Transition state theory) (Activated complex)

5 A + BC AB + C

A BC (A----B----C) AB C = Ea (E7.

(Endothermic reaction) (Exothermic reaction)

6 (N2 + O2) E1 (NO2) E3 (E E3 E1((E ) Ea E2 E1

7 (N2 + H2) E1 (NH3) E3 (E E3 E1 ((E ) Ea E2 E1 (Ea) ((E) 8. (Reaction mechanism)

5Fe2+(aq) + MnO4-(aq) + 8H+(aq)

5Fe3+(aq) + Mn2+(aq) + 4H2O(l) Fe2+ 5 mol, MnO4- 1 mol H+ 8 mol 14 mol 14 mol (Elementary process) (Elementary reaction)

1. (Unimolecular process) N2O4 2NO2 r = k[N2O4]

2. (Bimolecular process) 2 NO + O2

NO3 r = k[NO][O2]

3. (Termolecular process) 3 2NO + Br22NOBr 3 r = k[NO]2[Br]

(Rate determining step)

2NO(g) + O2(g) 2NO2(g) r = k[NO]2[O2] NO2 O2

2NO(g) + O2(g) 2NO2(g) 3

N2O2 (Intermediate)

r = k[N2O2][O2] N2O2 [N2O2] [N2O2]

[N2O2] r = k[N2O2][O2] r = k.K[NO]2[O2] = k[NO]2[O2]

NO + O2 NO3

(, )

NO3 + NO 2NO2()r = k[NO3][NO] NO3 [NO3]

[NO3] r = k[NO3][NO]

r = k.K[NO]2[O2]= k[NO]2[O2] 9.

8

8 A B 2 A X Ea1(E3 E1) Ea3 X A X B Ea2(E4 E2) Ea4 B X 1 2 1 2 1 1 X A (Ea3 = E3 E2) X B (Ea2 = E4 E2) 1 2 X B (Ea2 = E4 E2) B X (Ea4 = E4 E5) (E (E1 E5)

1

A X

..( )

2

X B

..()10.

10.1 H2 F2 H2 I2

H2(g) + F2(g) 2HF(g)..

H2(g) + I2(g) 2HI(g)

..

10.2

NO2(g) + CO(g)

CO2(g) + NO(g)

NO CO r = k[NO]2 2 CO

NO2 + NO2

NO3 + NO..

NO3 + CO

NO2 + CO2..NO2(g) + CO(g)

CO2(g) + NO(g)

10.3 (Heterogeneous reaction)

Mg(s) + 2HCl(aq)

MgCl2(aq) + H2(g)

Mg HCl HCl Mg Mg

10.4 1

10.5 ()

10 T1 T2 (T2) (Ea) (T1) (Svante August Arrhenius)

(Arrhenius Equation)

k (rate constant)

Ea(kJ/mol)

R = 8.314 J/mol.K

T(K)

A(frequency factor) A

k = Ae-Ea/RT log log k = log A Ea / 2.303RT

(1)

(slope) = Ea / 2.303RT(1) T1 T2 k k1 k2 k

log k1 = log A Ea / 2.303RT1

(2)

log k2 = log A Ea / 2.303RT2

(3)

(3) (2)

log k2 log k1 = (log A Ea / 2.303RT2) (log A Ea / 2.303RT1)

= Ea / 2.303RT1 - Ea / 2.303RT2

= (Ea / 2.303R) (1/T1 1/T2)

Log k2/k1 = (Ea / 2.303R) {(T2 T1)/T1T2}

10.6

(Catalyst) 2

1. (Homogeneous catalyst) I-(aq) H2O2(aq)

2H2O2(aq)

2H2O(l) + O2(g)

I-(aq) 2

1

H2O2(aq) + I-(aq) H2O(l) + IO-(aq)

2

IO-(aq) + H2O2(aq)

H2O(l) + O2(g) + I-(aq)

2H2O2(aq)

2H2O(l) + O2(g)

11 2H2O2(aq)

2H2O(l) + O2(g)

Ea1 1 , Ea2 2 , Ea3 Ea

2. (Heterogeneous catalyst) (Ni) H2 (C2H4)

12 C2H6

(H2 C2H4) (a) H H H H C 2 C2H4 (b, c) C2H6 (d)

(Substrate) (Enzyme substrate complex) (Product)

E + S

ES

E + P

E

S

ES

P

13

14

14 (Ea1) ((E1) (Ea2) ((E2)

(Inhibitor) (H2O2)

2H2O2(l) 2H2O(l) + O2(g)

15

(Ea2>Ea1) ((E)

=

=

( r ) = A = = --

A

([A]

(t

= B = = --

B

([B]

(t

= C = = +

C

([C]

(t

= D = = +

D

([D]

(t

= N2

= 1/3 H2

= 1/2 NH3

=1/c C= +1/c

([C]

(t

=1/d D= +1/d

([D]

(t

r=1/a A=--1/a

([A]

(t

([B]

(t

=1/b B=--1/b

Mg(s) + 2HCl(aq)MgCl2(aq) + H2(g)

=

=

2 NO2

( 3 )/( 2 ) ; =

0.084

0.021

k[0.02]x[0.03]y

k[0.01]x[0.03]y

k[0.01]x[0.02]y

k[0.01]x[0.01]y

( 5 )/( 4 ) ; =

0.014

0.007

3

NO(g) + CO(g) NO(g) + CO2(g)

(E)

N2(g) + O2(g)

2NO(g)

Ea

(E

E1

E2

E3

6 N2(g) + O2(g) 2NO(g)

(E)

N2(g) + 3H2(g)

2NH3(g)

Ea

(E

E3

E1

E2

7 N2(g) + 3H2(g) 2NH3(g)

2NO N2O2 (, )

N2O2 + O2 2NO2()

[N2O2]

K =

[N2O2] = K[NO]2

[NO]2

K =

[NO3] = K

[NO][O2]

[NO3]

[NO][O2]

(E)

E1

E2

E3

E4

E5

A

X

B

Ea4

Ea1

Ea2

Ea3

A B

(E

(a)

(b)

9 (a) (b)

(T2)

(T1)

Ea

T1 > (T2)

k = Ae-Ea/RT

Ea1

Ea2

2

Ea3

(Ea

2H2O2

2H2O + O2

E1

E2

Ea1

Ea2

( E

Ea1

Ea2

(E

PAGE 69.