2552
RMUTL
RATE OF CHEMICAL REACTION
CHEMISTRY FOR ENGINEERS
| CHOLLADA
KULWAT
RATE OF CHEMICAL REACTION
2552
6 ภภภ(Rate of Chemical Reaction) ภ!ภ" #$% &#'()*ภ* *+ ,-./ (rate of chemical reaction) ,(123&2'4*5 62!7'&#'4*5 ,-./ , /+ภ48 9:2 ;% <,-./ (chemical kinetics 6 ?# dynamics) B!7' !ภ" ภ4$C#$% &#'()*ภ* *+ 3:D (E99$+ (factor) %8 'FG/7./#*GH*I: 6 ?#./J:%8##$% &#'()*ภ* *+ 2$K2 LCM3ภ8 â&#x20AC;˘ H .5 %*&#'; %$K'%M2 (reactants) 3:D J:*%N$OP< (products) â&#x20AC;˘ -4 .,&M.&M2&#'; %$K'%M23:DJ:*%N$OP< â&#x20AC;˘ #SO6NT.* â&#x20AC;˘ #*GH*I:&#'; 9 ภN +2#ภ,582 %$4, 8'()*ภ* *+ (catalysts) 6 ?#%$46284' ()*ภ* *+ (inhibitors) 9 ภ#$% G/74$CLCM3:Dภ!ภ" V!'(E99$+G/7./#*GH*I:%8#()*ภ* *+ GW X6M,ภ*C-4 .,&M X948 ,6%SXC()*ภ* *+ 62!7'9!',ภ*C5M ;842#/ภ()*ภ* *+ 62!7',ภ*C, Y4 3:D,&M X9V!' +:D,#/+C6 ?#&$K2%#2 (step) &#'ภ,(:/7+23(:'G/7,ภ*Cภ$Z; %$K'%M292V!'ภ,ภ*CJ:*%N$OP< B!7', /+ภ48 ภ:Lภ&#'()*ภ* *+ (reaction mechanism) #$2,(12I?K2[ 2G/72$ภ,-./;2X9 3:DI+ + . !ภ" ภภภภภ-?# ภ!ภ" -4 .;$.I$2H< D648 ' ( *. O; G/7 ,(:/7+23(:' ภ$Z ,4: G/7X5MX2ภ,(:/7+23(:'2$K2 VM N +X2,4: G/7ภW 62C ( *. O; ,(:/7+23(:'L(9 ภ,C*.. ภ3;C'48 #$% ภ,(:/7+23(:'./-8 . ภภ3Z8'##ภ,(12 3 ( D,NG LCM3ภ8 1. ภ,(:/7+2;V 2D 2. ภ:D: +,(12; :D: + 3. ภ,ภ*C()*ภ* *+ ,-./ ;W 6 $Z6284+, /+22/K 9D,2M2, ?7#' ภ,ภ*C()*ภ* *+ ,-./
6.1
ภ-?# ภ,(:/7+23(:'G/7GW X6M,ภ*C; X6.8 ,&/+2;.ภ3;C'LCM C$'2/K ; %$K'%M2 â&#x2020;&#x2019; ; X6.8 6 ?# ; J:*%N$OP< (reactant) (product)
213
RATE OF CHEMICAL REACTION
2552
()*ก* *+ ,-./ 3Z8'% .:$ก"OD,2?K#; X2 DZZLCM,(12 2 3ZZ -?# 6.1.1 ก
(homogeneous reaction) ,(12()*ก* *+ G/7; GSก%$4X2 DZZ 4.,(12,2?K#,C/+4ก$2 ,582 N2 (g) + 3H2 (g) → 2NH3 (g) Cl2 (g) + 2NaOH (aq) → NaCl (aq) + NaClO (aq) + H2O (l) 6.1.2 ก (heterogeneous reaction) ,(12()*ก* *+ G/7; GSก%$4X2 DZZL.8 4.,(12,2?K#,C/+4ก$2 ,582 Mg (s) + 2HCl (aq) → MgCl2 (aq) + H2 (g) Zn (s) + CuSO4 (aq) → ZnSO4 (aq) + Cu (s ) X2&ODG/7()*ก* *+ กW :$'CW ,2*2L( L.848 9D,(12()*ก* *+ ,2?K#,C/+46 ?#()*ก* *+ ,2?K#J;. ( *. O; %$K'%M29D-8#+F:C:' 3%8( *. OJ:*%N$OP<9D-8#+F,I*7.&!K2 3:D( *. O; %$K'%M2G/7 :C:' ก$Z( *. OJ:*%N$OP<G/7,I*7.&!K2 9D./-4 .;$.I$2H<ก$2 -?# VM ; %$K'%M2:C:'#+8 ' 4C, Y4 3;C'48 ()*ก* *+ 2$K2,ก*C, Y4 J:*%N$OP<กY9D,I*7.&!K2#+8 ' 4C, Y4CM4+ C$'2$K2 ก ก ก
ก ก ก กYLCM
6.2
ก ก ก 6. +V!' !" ก # ก ก $ 1
' ( * ) " $ 1 ' ( ก ก ก =
( *. OJ:*%N$OP<G/7,ก*C&!K2 ( *. O; %$K'%M2G/7:C:' = ,4: ,4:
ก 4$C#$% ก ,ก*C()*ก* *+ 9D4$C9 ก( *. O&#'J:*%N$OP<G/7,ก*C&!K2 6 ?# ( *. O&#' ; %$K'%M2G/7:C:' &!K2#+T8ก$Z:$ก"OD&#'&M#.T:G/7./#+T8 3%8 ก ก
ก ก ! " ก ก
ก # ก
214
RATE OF CHEMICAL REACTION
ก. &. -. '.
2552
6.2.1 , - , ก ก ก &!K2#+T8ก$Z52*C&#'()*ก* *+ ,582 4$C#$% ก ,ก*C()*ก* *+ 9 ก( *. % 6 ?#-4 .C$2G/7,(:/7+23(:'L( X2 DZZG/7./3กf; 4$C#$% ก ,ก*C()*ก* *+ 9 ก;/&#' DZZG/7,(:/7+23(:'L( 4$C#$% ก ,ก*C()*ก* *+ 9 ก-4 .,&M.&M2&#'; :D: +G/7,(:/7+23(:'L( 4$C9 ก( *. O&#'&#'3&Y'G/7,ก*C&!K2 g:g
, . / 6.1 9 ก()*ก* *+ %8#L(2/K ; . V4$C#$% ก ,ก*C()*ก* *+ LCM#+8 'L ZM ' 2KMnO4 (aq) + 16HCl (aq) → 2KCl (aq) + 2MnCl2 (aq) + 7H2O (l) + 5Cl2(g) # 99D4$C#$% ก ,ก*C()*ก* *+ LCMC$'%8#L(2/K ก. 4$C9 ก;/&#' KMnO4 G/79 '6 +L( &. 4$C9 ก pH &#'; :D: +G/7,I*7.&!K2 -. 4$C9 ก( *. % 6 ?# -4 .C$2&#'3กf; Cl2 G/7,ก*C&!K2 '. 4$C9 ก-4 .,&M.&M2&#'; :D: +%8 'F ,582 HCl , KMnO4 ,(12%M2 6.2.2 ก 0 ,1 ก ก ก I*9 O LCM9 ก;.ก G/7(l*ก* *+ 2$K2,ก/7+4&M#' mC+X5Mm.:,&M 584+ , . / 6.2 X2()*ก* *+ %8#L(2/K Mg + 2HCl → MgCl2 + H2 9 กก GC:#'IZ48 ,.?7#X;8 Mg 5*K262!7':'X2ก C HCl 9W 242. ก,ก*2I# 6:$'9 ก,4: J8 2L( 5 2 G/ ( ก)48 Mg :C:' 4.8 ก $. ก. 9'-W 24O#$% ก ,ก*C H2 3:D#$% ก :C:'&#' HCl ,(12 m.:/2 G/ &. 9'-W 24O#$% ก ,ก*C()*ก* *+ ,(12 m.:/2 G/
4 .8 = 0.2 m.: 24 ∆[Mg ] 0.2 = = 0.04 m.:/2 G/ ∆t 5 #$% ก :C Mg = 0.04 m.:/2 G/ 2 #$% ก :C Mg = 0.08 m.:/2 G/ #$% ก :C Mg = 0.04 m.:/2 G/
9 กm9G+<X2,4: 5 2 G/ Mg :C:' 4.8 ก $. = #$% ก :C:'&#' Mg
=
ก. #$% ก ,ก*C H2 = #$% ก :C HCl = &. #$% ก ,ก*C()*ก* *+ =
215
RATE OF CHEMICAL REACTION
2552
1 1 6 ?##$% ก ,ก*C()*ก* *+ = #$% ก :C HCl = × 0.08 = 0.04 m.:/2 G/ 2 2 9D,6Y2LCM48 #$% ก ,ก*C()*ก* *+ 9D%M#'./-8 ,G8 ก$2 3.M48 #$% ก ,(:/7+23(:' ( *. O&#'; %8 ' F 9DL.8,G8 ก$2 6.2.3 3 4 5 / ก ก ก 3Z8',(12 2 ( D,NG -?# 1. #$% ก ,ก*C()*ก* *+ ,q:/7+ 2. #$% ก ,ก*C()*ก* *+ &ODXC&OD62!7' B!7'#$% ก ,ก*C()*ก* *+ G$K' 2 52*C9DL.8,G8 ก$2 X2%#2%M2 F &#'()*ก* *+ #$% ก ,ก*C()*ก* *+ O &ODXC&OD62!7' 9D;T'ก48 #$% ,q:/7+ 3%8X2584'GM + F 9D5M ก48 #$% ,q:/7+ #$% ก ,ก*C()*ก* *+ X2,G#.&#'ก r # 99D,&/+2ก rmC+% ' D648 ' #$% ก ,ก*C()*ก* *+ ก$Z,4: 6 ?# D648 '-4 . ,&M.&M2ก$Z,4: ,582()*ก* *+ A → B ,(12ก r3;C'#$% ก ,ก*C()*ก* *+ LCMC$'2/K
6 6.1 7 6 5. ก ก ก 89 ก : ก 1; A * B 9 < 9/ =/ 7 1 ., ,9 <93 ก ก ก 5137 513 > / * . , ? 5 /ก @ (slope) 5 /ก @ 1 ,9 = A
, . / 6.3 ,.?7#2W ; 3 52*C A , B , C ( *. O,G8 ก$2. J;.ก$2 ,.?7#,4: J8 2L( % 496 ( *. O&#'; G$K' 3 LCMC$'X2 T( 9 ก T( 6. +-4 .48 #+8 'L ก. A + B → C &. B + C → A -. C → A '. A + C → B
216
RATE OF CHEMICAL REACTION
2552
9 กก r 9D,6Y2LCM48 ,.?7#,4: J8 2L(; A 9D. ก&!K2 3%8; C :C:' X2&ODG/7; B ,G8 ,C*. 3;C'48 ; B L.8,ก*C()*ก* *+ #$% ก ,(:/7+2-4 .,&M.&M29!',(12 T2+< ; A ,I*7. 3;C' 48 ,(12J:*%N$OP< C$'2$K2 ()*ก* *+ -?# C → A .............................................(-) , . / 6.4 ;W 6 $Z()*ก* *+ 2H2O2 (aq) → 2H2O (l) + O2 (g) B!7',ก*C&!K2X2 DZZ(tC #$% ก ;: +%$4&#'LumC ,92,(# <##กLBC< (4$C9 ก( *. % &#'3กf; O2 G/7,ก*C&!K2) ,(:/7+2L(% .,4: C$'ก r T(XC
,2?7#'9 ก,ก*CX2 DZZ(tC 9!'./N 4D;.CS:,ก*C&!K2 #$% ก ;: +%$4&#' H2O2 X2 %#23 ก9D./-8 . ก 3:D-8#+F2M#+:'% .:W C$Z 92V!';.CS: GW X6M#$% ก ,ก*C O2 B!7'LCM9 กก ;: +%$4&#' H2O2 ./-8 . กX2%#23 ก 3:M4-8#+F:C:' ! $ ก. #&'" " ( ) ก * + ,- " #&' ' . 6.2.4 C:: D9 . ก ก ก
217
RATE OF CHEMICAL REACTION , ; . V-4Z-S.#$% ก ,ก*C()*ก* *+ X6M, Y4&!K26 ?#5M :'กYLCM
2552
CM4+ก -4Z-S.(E99$+
%8#L(2/K 1. 52*C&#'; %$K'%M2 2. -4 .,&M.&M2&#'; %$K'%M2G/7,(12; :D: +6 ?#กf B 3. I?K2G/7J*4&#'&#'3&Y'6 ?#&#',6:4X2()*ก* *+ ,2?K#J;. 4. #SO6NT.* 5. %$4, 8'6 ?#%$46284'()*ก* *+ 6.2.4.1 ? 5 /; =/ ก ก ก ก 4Ag(s) + O2(g) → 2Ag2O(s) 2Cu(s) + O2(g) → 2CuO(s) 2Mg(s) + O2(g) → 2MgO(s) 4Na(s) + O2(g) → 2Na2O(s)
5M . ก 5M , Y4 , Y4. ก, D,Z*C
X2()*ก* *+ 52*C,C/+4ก$2 3%8X5M; %$K'%M2%8 '52*Cก$2 9D,ก*C()*ก* *+ LCM, Y4L.8,G8 ก$2 ,582 ()*ก* *+ D648 'm:6D ก$Z ##กB*,92 ,ก*C,(12m:6D##กLBC< G#'3C'6 ?#,'*2 9D,ก*C()*ก* *+ 5M . ก,.?7#,J 4.ก$Z##กB*,92 X2&ODG/7VM ,(:/7+2,(123.ก2/,B/+.9D%*CLr#+8 ' 4C, Y4 3:DVM ,(12 m:6DmB,C/+.9D%*CLrLCM,#'#+8 ' 4C, Y4X2# ก , Y4. ก Ag+(aq) + Cl-(aq) → AgCl(s) Mg2+(aq) + C2O42- (aq) → MgC2O4(s) 5M Na+(aq) + Cl-(aq) → NaCl(s) 5M . ก 3%8; %$K'%M252*C,C/+4ก$2 ,.?7#,(:/7+2:$ก"OD&#'()*ก* *+ ,-./ #$% ก ,ก*C()*ก* *+ กY9D ,(:/7+2L(9 ก,C*. ,582 Ag+ 9D%กJ:!ก,(12 AgCl LCM, Y4. ก,.?7#GW ()*ก* *+ ก$Z Cl- X2&ODG/7 Na+ %กJ:!ก,(12 NaCl LCM5M . ก 6.2.4.2 D95 / , 5 5 ก ก ก ก mC+G$74 F L( ,.?7#,I*7.-4 .,&M.&M2&#'; %$K'%M2 9DGW X6M#$% ก ,ก*C()*ก* *+ ,I*7.&!K2 ก I*9 O 48 -4 .,&M.&M2&#'; XCZM './J:%8##$% ก ,ก*C()*ก* *+ 3:D./J:. ก2M#+,I/+'XC I*9 O LCM9 กJ:ก GC:#' 3:D-W 24OmC+# $+กl#$% , Y4,&M 584+
218
RATE OF CHEMICAL REACTION ) " +
2552
ก ก
ก )/ $ก ," ) ) ) ! , กก # # 0 ก ก
กE F, X5M3;C'-4 .;$.I$2H< D648 ' ก ก ก ก$Z ) ) ) mC+ ก:8 4L4M48 1 ก ก
ก 2 3 ก ," ) ) ) 4 ,582
()*ก* *+ aA + bB → cC 9DLCM R ∝ [A]m 3:D R ∝ [B]n 6 ?# R ∝ [A]m[B]n R = k[A]m[B]n R -?##$% ก ,ก*C()*ก* *+ [A],[B] -?#-4 .,&M.&M2&#'; A 3:D B % .:W C$Z m , n -?##$2C$Z&#'()*ก* *+ ,G/+Zก$Z A 3:D B % .:W C$Z m + n -?##$2C$Z 4.&#'()*ก* *+ (m # 99D,G8 ก$Z a 6 ?#L.8,G8 กYLCM ,582,C/+4ก$Z n B!7'# 99D,G8 ก$Z b 6 ?#L.8กYLCM G$K'2/K9D%M#'LCM 9 กก GC:#') k -?#-8 -'G/7#$% , Y4&#'()*ก* *+ ก กE F, VM ./; %$K'%M2 2 52*C 9D./%$43( G/7L.8G Z-8 3 %$4 -?# k , m 3:D n C$'2$K29!'%M#'GC:#' #+8 '2M#+ 3 ก GC:#' mC+,:?#ก-4 .,&M.&M2%8 'Fก$2 ,I?7#2W . 3G2-8 :'X2;.ก &#'กl #$% , Y4 3:M43กM;.ก 6 -8 k , m 3:D n -8 &#' m 3:D n 9DZ#กX6MG Z48 #$% ก ,ก*C()*ก* *+ &!K2#+T8ก$Z; XCZM ' . ก2M#+ ,G8 XC &!K2#+T8ก$Z-4 .,&M.&M2&#'; XC. กก48 ,582 VM 9 กJ:ก GC:#',&/+2;.ก LCM,(12 2NO + O2 → 2NO2 LCM-8 m = 2 , n = 1 3;C'48 R = k[NO]2 [O2] X2ก O/2/KG$K'; NO 3:D O2 9D./J:%8##$% ก ,ก*C()*ก* *+ mC+G/7 NO ./J:. กก48 O2
219
RATE OF CHEMICAL REACTION
2552
J:Z4ภD648 ' m ภ$Z n , /+ภ48 * ภ(order of the reaction) X2()*ภ* *+ 2/K , /+ภ48 ()*ภ* *+ #$2C$Z; . (third order) ,I DJ:Z4ภ&#',:&+ภภW :$' (2 + 1) ,G8 ภ$Z 3 3:D# 9 , /+ภ()*ภ* *+ #$2C$Z;#' (second order) ,.?7#,G/+Zภ$Z NO 3:D, /+ภ48 ()*ภ* *+ #$2C$Z62!7' (first order) ,.?7#,G/+Zภ$Z O2 , . / 6.5 ()*ภ* *+ ,ภ*C&!K2C$';.ภA + 2B â&#x2020;&#x2019; C 3:D./J:ภGC:#'C$'2/K ภ9 / [A] mol/l [B] mol/l ภภ5 / C mol/l-sec 1 1.0 1.0 2.5 2 2.0 1.0 2.5 3 1.0 2.0 2.5 ภ. #$% ภ,ภ*C&#' C ./-4 .;$.I$2H<ภ$Z-4 .,&M.&M2&#' A 3:D B #+8 'L &. X2ภGC:#'G/7 1 VM :C( *. O&#'; %$K'%M2X6M,6:?#,I/+'- !7'62!7'9D./J:%8#ภ,ภ*C&#' C #+8 'L
ภ.
I*9 O 9 ภภl#$% , Y4 R = k[A]m[B]n 9 ภภGC:#'G/7 1 ; 2.5 = k[1.0]m[1.0]n ....................................(1) 9 ภภGC:#'G/7 2 ; 2.5 = k[2.0]m[1.0]n ....................................(2) 9 ภภGC:#'G/7 3 ; 5.0 = k[1.0]m[2.0]n ....................................(3) 2.5 k[2.0] m [1.0] n 5.0 k[1.0]0 [2.0] n m n 2 á1; = 3á2; = m n â&#x2021;&#x2019; 1 = (2) 0 n â&#x2021;&#x2019; 2 = (2) 2.5 k[1.0] [1.0] 2.5 k[2.0] [1.0] â&#x2C6;´m = 0 â&#x2C6;´n = 1 0 2.5 = k[1.0] [1.0]1 â&#x2021;&#x2019; 2.5 = k â&#x2C6;´ k = 2.5 9 ภ(1) , (2) , (3) ; m = 0 , n = 1 , k = 2.5 â&#x2C6;´ R = k[B] = 2.5[B] #$% ภ,ภ*C&#' C ,(12 2.5 ,G8 &#'-4 .,&M.&M2&#' B &. 9 ภภGC:#'G/7 1 ,.?7# [A] = 0.5 , [B] = 0.5 R = 2.5 (0.5) = 1.25 mol/l-sec C$'2$K2 #$% ภ,ภ*C&#' C 9D:C:'- !7'62!7' 220
RATE OF CHEMICAL REACTION
2552
, . / 6.6 9 กก 4$C#$% ก ,ก*C()*ก* *+ 2P + Q → 2R LCMJ:C$'2/K ก 9 / [P] mol/l [Q] mol/l R mol/l-sec 1 0.1 0.1 1.0 × 10-6 2 0.5 0.4 1.6 × 10-3 3 0.2 0.3 1.08 × 10-4 4 0.4 0.3 4.32 × 10-4 ก. 9'6 กl#$% , Y4 &. 9'-W 24O-8 -'G/7#$% , Y4 -. VM [P] = 0.3 mol/l 3:D [Q] = 0.2 mol/l 9D./#$% ก ,ก*C()*ก* *+ ,(12,G8 XC
ก. 9 ก R = k[P]m[Q]n 9 กก GC:#'G/7 1 ; 1.0 x 10-6 = k[0.1]m[0.1]n ....................................(1) 9 กก GC:#'G/7 3 ; 1.08 x 10-4 = k[0.2]m[0.3]n ....................................(2) 9 กก GC:#'G/7 4 ; 4.32 x 10-4 = k[0.4]m[0.3]n ....................................(3) 4.32 ×10 -4 k[0.4] m [0.3] n m 3÷2; -4 = m n ⇒ 4 = (2) 1.08 ×10 k[0.2] [0.3] ∴m = 2 1.08 ×10 -4 k[0.2] 2 [0.3] n n n 2 ÷1; -6 = 2 n ⇒ 108 = 4(3) ⇒ 27 = (3) 1.0 ×10 k[0.1] [0.1] ∴n = 3 9 ก (1) , (2) , (3) ; m = 2 , n = 3 ∴ R = k[P]2[Q]3 &. 9 ก (1) 1.0 x 10-6 = k (0.1)2(0.1)3 k = 0.1 R = 0.1(0.3)2(0.2)3 -. 221
RATE OF CHEMICAL REACTION =
7.2 x 10-5
2552
mol/l-sec
, . / 6.7 9 ก()*ก* *+ 2H2 + 2NO → 2H2O + N2 ./J:ก GC:#'C$'2/K 1. VM ,I*7. [H2] 2 ,G8 #$% ก ,ก*C()*ก* *+ ,I*7. 2 ,G8 2. VM ,I*7. [NO] 2 ,G8 #$% ก ,ก*C()*ก* *+ ,I*7. 4 ,G8 3. VM ,I*7. [H2] 3 ,G8 #$% ก ,ก*C()*ก* *+ ,I*7. 3 ,G8 4. VM ,I*7. [NO] 3 ,G8 #$% ก ,ก*C()*ก* *+ ,I*7. 9 ,G8 9'6 กl#$% , Y4 R = k[H2]m[NO]n [H2] = x , [NO] = y R = k[x]m[y]n .........................................(1) 9 ก 1 ; 2R = k[2x]m[y]n .......................................(2) 9 ก 2 ; 4R = k[x]m[2y]n .......................................(3) 2R k[2x] m [y] n m 2 ÷1; = m n ⇒ 2 = (2) R k[x] [y]
9 ก X6M, *7.%M2./
∴m = 1 4R k[x]1 [2y] n (2) n 3÷2; = ⇒ 4 = (2) n 1 n ⇒2 = 2R k[2x] [y] 2 ∴n = 2 9 ก (1) , (2) 3:D (3) LCM m =1 , n = 2 ∴ R = k[H2][NO]2 ก T : 1 ก ก ก 7 5 /ก @ VM ,(12()*ก* *+ #$2C$Z62!7' ,582 R = k[A] ,.?7#,&/+2ก r D648 ' R ก$Z [A] -4 9DLCM ก r,;M2% 'J8 29SCกW ,2*C 3:D./-4 .5$2 = k
222
RATE OF CHEMICAL REACTION
2552
6 6.2 ก @ 3 ,. / ก ก ก ( R ) ก , 5 5 5 /; A ( [A] )
6.2.4.3 D95 /T*= D , . ก ก ก ,qI DX2()*ก* *+ ,2?K#J;. B!7'; %$K'%M2L.8LCM 4.,(12,2?K#,C/+4ก$2,G8 2$K2 G/7I?K2G/7J*4./J: %8##$% ก ,ก*C()*ก* *+ +*7'; %$K'%M2./I?K2G/7J*4. ก,G8 XC กY+*7'9D,ก*C()*ก* *+ LCM, Y4. ก&!K2,G8 2$K2 ,I D()*ก* *+ 9D,ก*C% ';842&#'J*4G/7;$.J$; ,582 VM 2W :4C Mg 1 5*K2 GW ()*ก* *+ ก$Zก C HCl 9W 242. ก,ก*2 I# 9D,ก*C()*ก* *+ 5M ก48 ,.?7#X5MJ' Mg 62$ก,G8 ก$2GW ()*ก* *+ ก$Zก C HCl ,I D Mg ก$Z HCl ,(12()*ก* *+ ,2?K#J;. ,.?7#X5MJ' Mg I?K2G/7J*49D. ก ()*ก* *+ 9!',ก*C, Y4 6.2.4.4 D95 / U1 46 . ก ก ก mC+G$74L( ,.?7##SO6NT.*,I*7.&!K2 #$% ก ,ก*C()*ก* *+ 9D,I*7.&!K2 3:D,.?7##SO6NT.*:C:' #$% ก ,ก*C()*ก* *+ 9D:C:' ,582 ก ,กYZ# 6 L4MX2%TM,+Y2 GW X6M# 6 ZTC,28 5M :' ,I DX2 %TM,+Y2./#SO6NT.*%7W 6.2.4.5 D95 / , ./ ก <93 , .,/ ก . ก ก ก 2#ก9 ก9D,I*7.#$% ก ,ก*C()*ก* *+ mC+ก ,I*7.-4 .,&M.&M2 ,I*7.#SO6NT.* 3:D,I*7.I?K2G/7 J*43:M4 +$'; . V,I*7.#$% ก ,ก*C()*ก* *+ LCMmC+,%*.; Z '#+8 'G/7, /+ก48 ( ก (catalyst) :'L( ,582 MnO
2 2KClO 3 (s) → 2KCl (s) + 3O 2 (g)
∆
VM ,J KClO3 9D,ก*C()*ก* *+ + ก 3%8VM X;8 MnO2 :'L(CM4+ 9DGW X6M,ก*C()*ก* *+ LCM O2 , Y4 &!K2 MnO2 -?# %$4, 8'()*ก* *+ ( ก 6. +V!' ; G/7584+GW X6M()*ก* *+ ,ก*CLCM, Y4&!K2 mC+G/7%$4, 8'()*ก* *+ 2$K2 # 99D./;842 84.ก$Z()*ก* *+ mC+% '6 ?#mC+#M#.กYLCM 3%8,.?7#()*ก* *+ ,ก*C&!K2;.ZT O<3:M4 9D%M#' LCMก:$Z-?2. ,G8 ,C*. 2#ก9 ก%$4, 8'()*ก* *+ 3:M4 +$'./ ' ( ก (inhibitor) B!7'GW X6M()*ก* *+ ,ก*C5M :' 223
RATE OF CHEMICAL REACTION
2552
, . / 6.8 ก GC:#'X2&M#XC ./#$% ก ,ก*C()*ก* *+ ;T'G/7;SCG/7#SO6NT.*,C/+4ก$2 ก. X;83J82;$'กD;/ 1 5*K2 62$ก 1 ก $. :'X2ก C HCl 0.1 mol/dm3 &. X;83J82;$'กD;/ 2 5*K2 62$ก5*K2:D 0.5 ก $. :'X2ก C HCl 0.2 mol/dm3 -. X;8;$'กD;/J':D,#/+C62$ก 1 ก $. :'X2ก C HCl 0.1 mol/dm3 '. X;8;$'กD;/J':D,#/+C62$ก 1 ก $. :'X2ก C HCl 0.2 mol/dm3
X2()*ก* *+ ,2?K#J;. 2#ก9 กก ,I*7.-4 .,&M.&M2 9DGW X6M#$% ก ,ก*C()*ก* *+ ,I*7.&!K2 3:M4 ก ,I*7.I?K2G/7J*4กYGW X6M#$% ก ,ก*C()*ก* *+ ,I*7.&!K2,582,C/+4ก$2 C$'2$K2ก X5MJ';$'กD;/ (,I*7.I?K2G/7J*4) 3:Dก X5M HCl 0.2 mol/l (,I*7.-4 .,&M.&M2) 9DGW X6M#$% ก ,ก*C()*ก* *+ ;T';SC...........................................................(') , . / 6.9 X2ก !ก" ()*ก* *+ ,-./mC+G$74L( .$ก%M#'ก X6M()*ก* *+ ,ก*C, Y4&!K2 C$'2$K2,4: GW ก GC:#' 9!'-4 9DGW #+8 'L ก. #S82X6M M#2 ,I?7#,I*7.#SO6NT.* &. X5M; :D: +./-4 .,&M.&M2;T' -. X5M4*H/-2#+8 ';.7W ,;.# '. X5M4*H/ก G$K' ก , & 3:D
ก ,I*7.#SO6NT.*3:Dก ,I*7.-4 .,&M.&M2 9DGW X6M()*ก* *+ ,ก*C, Y4&!K2 2#ก9 ก2/KX2G ' ()*Z$%* +$'%M#'./ก -2; :D: +#+8 ';.7W ,;.# ,I?7#GW X6M; %$K'%M2GW ()*ก* *+ ก$2C/&!K2 ,(12ก ,I*7.#$% ก ,ก*C()*ก* *+ ,582,C/+4ก$2...........................................................(')
6.3
XYE 7? - ก ก ก 224
RATE OF CHEMICAL REACTION
2552
XYE ก ? ก 5 /Z 9กU9 ,(12G~"l/G/7X5M#H*Z +48 ()*ก* *+ ,-./,ก*C&!K2LCM#+8 'L ,I?7#G/79D#H*Z +LCM48 ,6%SXC#$% ก ,ก*C()*ก* *+ 9!'&!K2ก$Z #SO6NT.* -4 .C$2 I?K2G/7J*4 -4 .,&M.&M2 4.G$K'%$4, 8'3:D%$46284' ()*ก* *+ X2()*ก* *+ ,-./ ; %$K'%M29D,(:/7+23(:'L(,(12J:*%N$OP<LCM กY%8#,.?7#m.,:กS:&#'; %$K' %M2./ก 52ก$2 ,582 H2 9DGW ()*ก* *+ ก$Z Cl2 ,ก*C,(12 HCl LCMกY%8#,.?7# H2 3:D Cl2 ./ก 52ก$2 +*7' 52ก$2Z8#+,G8 L กY+*7'./m#ก ;,ก*C()*ก* *+ LCM. ก,G8 2$K2 3%8X2&ODG/7,ก*C()*ก* *+ ,-./ 9D./G$K'ก ;: +3:Dก ; M 'I$2HD C$'()*ก* *+ H2(g) + Cl2(g) → 2HCl(g) 9D./ก ;: +I$2HD H2(g) 3:D Cl2(g) H2(g) → 2H(g) CTCI:$'' 2 Cl2(g) → 2Cl(g) 3:M49!'./ก ; M 'I$2HD D648 ' H ก$Z Cl 2H(g) + 2Cl(g) → 2HCl(g) - +I:$'' 2 C$'2$K2
ก " & ก )/ ' . ") ) ( ก CM4+-4 .3 ' I#G/79DGW X6MI$2HD,C*.;: +##ก m.,:กS:&#'; %$K'%M2G/752ก$2#+8 '3 ' 9D%M#',(12m.,:กS: ,-:?7#2G/7#+8 ' 4C, Y4 (m.,:กS:G/7,-:?7#2G/75M 9D52ก$2,Z F) 3;C'48 ./I:$'' 29:2<;T' C$'2$K2 m.,:กS:G/7./I:$'' 29:2<%7W F ,.?7#52ก$2 9DL.8GW X6M,ก*C()*ก* *+ 3%8m.,:กS:G/7./I:$'' 29:2<;T' F ,.?7#52ก$2 9DGW X6M,ก*C()*ก* *+ LCM , /+กI:$'' 29:2<G/72M#+G/7;SCG/7GW X6M,ก*C()*ก* *+ ,-./48 0 ก . (Energy of activation ; Ea) B!7',(12-8 ,qI D ;W 6 $Z()*ก* *+ 62!7' F #+8 'L กY% . ,.?7#m.,:กS:&#'; %$K'%M252ก$2CM4+I:$'' 2#+8 '2M#+,G8 ก$ZI:$'' 2 ก D%SM2 # 9L.8,ก*C()*ก* *+ ,-./กYLCM &#X6M;$',ก% T(%8#L(2/K
225
RATE OF CHEMICAL REACTION
2552
6 6.3 7 ก ก ก 3 ,. /Z 9กU95 / CN < .93Z 9กU9 / T9 // 3; ]>/ * ? ก <9 , 0 7 ก ก ; ;3 * ^ D97 T -3 ;9 [
6 6.4 _ /5 /ก ? [ . 3;
6 6.5 _ /5 /ก ? 3;
9 ก T( 3;C'X6M,6Y248 ()*ก* *+ ,-./9D,ก*C&!K2LCM ,.?7#m.,:กS:&#'; %$K'%M252ก$2X2 G* G 'G/7,6. D;. ,582 ()*ก* *+ D648 ' H2O ก$Z CO ,&/+2;.ก 3;C'LCMC$'2/K H2O + CO → H2 + CO2 G* G 'ก 529D%M#',(12C$'2/K VM G* G 'ก 52,(123ZZ#?729DL.8,ก*C()*ก* *+ 3:D2/7,(12,6%SJ:#/ก#+8 '62!7'G/748 GW L.#$% ก 52ก$2&#'#2SN -9!'. กก48 #$% ก ,ก*C()*ก* *+ ; U XYE ก ? ก 5 /Z 9กU9 ()*ก* *+ 9D,ก*C&!K2,.?7# 1. m.,:กS:&#'; %$K'%M252ก$2 2. m.,:กS:G/752ก$2%M#'./I:$'' 2#+8 '2M#+,G8 ก$ZI:$'' 2ก D%SM2 3. G* G 'X2ก 52%M#',6. D;.
6.4
T9 // ก ก 0 [ 5 / ก
,.?7#,ก*C()*ก* *+ ,-./ DZZ# 99DCTC6 ?#- +I:$'' 2กYLCM mC+I:$'' 2G/7V8 +,G D648 ' DZZก$Z;*7'34C:M#. กY-?# I:$'' 2-4 . M#2 B!7'9Dก DGZก D,G?#2I:$'' 2 $ก+<&#' DZZCM4+
226
RATE OF CHEMICAL REACTION
2552
6.4.1 ก ) ,.?7#,ก*C()*ก* *+ ,-./3:M4 DZZ9D M#2&!K2 9!'- +-4 . M#2X6M;*7'34C:M#. mC+-4 . M#2G/7 DZZ- +##กL( ,(12-4 . M#2G/7,(:/7+2 T(. 9 กI:$'' 2 $ก+< C$' T(G/7 6.6
6 6.6 ก 3 4 = ; D9 4 1`a:3 T9 // _ ก a ก,. ; =/
6.4.2 ก < ) ,.?7#,ก*C()*ก* *+ ,-./3:M4 DZZ9D,+Y2:' 9!'CTC-4 . M#2 9 ก;*7'34C:M#. mC+-4 . M#2G/7 DZZCTC,&M 9DVTก,(:/7+2,(12I:$'' 2 $ก+<,กYZ,# L4M C$' T(G/7 6.7
6 6.7 ก 3 4 = ; D9 4 1`a:3 T9 // _ ก a;6/ก,. ; =/ %M2
227
RATE OF CHEMICAL REACTION
2552
9D,6Y2LCM48 ก8#23:D6:$',ก*C()*ก* *+ ,-./ DZZ9D./I:$'' 2 $ก+<L.8,G8 ก$2 2#ก9 ก2/K &OD,ก*C()*ก* *+ กY./ก ,(:/7+23(:'I:$'' 2 $ก+<CM4+ ,I D9D./()*ก* *+ ,ก*C&!K2LCM กY%8#,.?7#; %$K'%M252ก$2#+8 '3 'CM4+I:$'' 29:2<#+8 '2M#+,G8 ก$ZI:$'' 2ก D%SM2 ,.?7#; %$K'%M2,-:?7#2G/7,&M 6 ก$2 9252ก$2 3:D3+ก##ก9 กก$2ก: +,(12J:*%N$OP< 9D./ก ,(:/7+23(:'I:$'' 2C$' T(G/7 6.8
m.,:กS:&#'; %$K'%M2G/79D,ก*Cก ,(:/7+23(:'L( ,(12J:*%N$OP<LCM %M#'./I:$'' 29:2<;T' -?#%M#'4*7', Y4 C$'2$K2I:$'' 2 $ก+<&#'m.,:กS:9D%7W ,.?7#m.,:กS:&#'; %$K'%M2,-:?7#2G/7,&M L(Xก:Mก$2 #*,:Yก% #2&#'3%8:Dm.,:กS:9DJ:$กก$2 GW X6M3%8:D m.,:กS:4*7',&M 6 ก$25M :' I:$'' 29:2<&#'m.,:กS: :C:' 3%8I:$'' 2 $ก+<,I*7.&!K2 m.,:กS:&#'; %$K'%M252ก$2 ,ก*C,(12m.,:กS: 5$74- 4G/7VTกก D%SM2 (activated complex) &OD2/K9D./ ก ,(:/7+2 3(:'I$2HDX6.8 D648 '#D%#.X2 m.,:กS:G$K';#' I:$'' 29:2<&#'m.,:กS:,(12 T2+< ,2?7#'9 ก,(:/7+2L(,(12I:$'' 2 $ก+<926.C ,.?7#,(:/7+23(:'I$2HD 92ก: +,(12; J:*%N$OP< 3:M4 m.,:กS:&#'; X6.89D3+ก##ก9 กก$2 I:$'' 2 $ก+<9D:C%7W :' I:$'' 29:2<9D,I*7.&!K2 6 6.8 ก 9 < 9/T9 // ก. <93 9 / ก ก
ก ,(:/7+23(:'I:$'' 2 $ก+<&OD,ก*C()*ก* *+ ,-./ ,&/+2ก r3;C'LCMC$'2/K
228
RATE OF CHEMICAL REACTION
A
B
C ∆Ea ∆H
2552
6 6.9 ก 9 < 9/T9 // 5 /; 513 ก ก 7 5 /ก @
" . ' m.,:กS:&#'; %$K'%M2+$'#+T868 'ก$2 3:D4*7',&M 6 ก$2#+8 ' 4C, Y4 I:$'' 2 $ก+<%7W 3%8I:$'' 29:2<;T' ,.?7#4*7',&M Xก:Mก$2 9D./3 'J:$ก,2?7#'9 ก#*,:Yก% #2&#'3%8:D m.,:กS: GW X6MI:$'' 29:2<-8#+ F :C:' 3%8I:$'' 2 $ก+<;T'&!K2 " . #&' ( ก 0 & ,ก*C,(12m.,:กS:5$74- 4G/7VTกก D%SM2 9SC2/KI:$'' 29:2<,(12 T2+< 3:DI:$'' 2 $ก+<./-8 . กG/7;SC ,I DI:$'' 29:2<G$K'6.CVTก,(:/7+2L(,(12I:$'' 2 $ก+< &OD2/KVM ./ก ; M 'I$2HDX6.89Dก: +,(12J:*%N$OP< 3%8VM I$2HD,C*.L.8 ,(:/7+23(:' กY9D+$'-',(12; %$K'%M2%$4,C*. " B!7'# 9./I:$'' 2 $ก+<;T'ก48 6 ?#%7W ก48 ; %$K'%M2กYLCM &!K2ก$Z52*C&#' ()*ก* *+ 48 ,(12()*ก* *+ CTC6 ?#- +-4 . M#2 " 0 E ก #&' 0 ' )/ B!7'กY-?#0 #&' 2$72,#' 3:DI:$'' 2;8422/K,#'G/7 , /+ก48 I:$'' 2ก D%SM2 " 0 )
ก
ก ก ก :3 F, * ? 7 </.5 / XYE &!K2#+T8ก$Z(E99$+ 2 #+8 ' -?# ก. #2SN -G/7./I:$'' 2;T' &. -8 I:$'' 2ก D%SM2&#'()*ก* *+ ()*ก* *+ G/7./#2SN -B!7'./I:$'' 2;T'F9W 242. ก 3:D./I:$'' 2ก D%SM2%7W 9D,ก*CLCM, Y4 ก48 ()*ก* *+ G/7./#2SN -B!7'./I:$'' 2;T'F 9W 2422M#+ 3:D./I:$'' 2ก D%SM2;T' +*7'./#2SN -G/7./I:$'' 2;T' F (,G8 ก$Z 6 ?# . กก48 I:$'' 2ก D%SM2) . ก,G8 XC กY9D+*7' ,ก*C()*ก* *+ LCM, Y4,G8 2$K2 3:D ()*ก* *+ +*7'./I:$'' 2ก D%SM2%7W ,G8 XC กY9D+*7',ก*CLCM, Y4&!K2,G8 2$K2
229
RATE OF CHEMICAL REACTION
2552
mC+G$74 F L( X2()*ก* *+ G/.7 / Ea %7W .$ก9D./9W 242m.,:กS:G/7./I:$'' 2;T' F 9W 242. ก 9!'GW X6M,ก*C()*ก* *+ LCM, Y4 X2G '% '&M . ()*ก* *+ G/7./ Ea ;T' 9D./9W 242m.,:กS:G/7./I:$'' 2;T' F #+T82M#+ 9!',ก*C5M
6.5
D95 / , 5 5 . ก ก ก
,.?7#-4 .,&M.&M2&#'; ,I*7.&!K2 #$% ก ,ก*C()*ก* *+ 9D,I*7.&!K2 ,2?7#'9 กก ,I*7.-4 . ,&M.&M2 กY-?# ก ,I*7.9W 242#2SN -G/79D,&M . 52ก$2 ,.?7##$% ก 52. ก&!K2 #$% ก ,ก*C()*ก* *+ 9!',I*7.&!K2LCM X2Z 'ก O/ก ,I*7.-4 .,&M.&M2# 99DL.8./J:%8##$% ก ,ก*C()*ก* *+ G$K'2/K&!K2#+T8ก$Z ก =ก ก ก9[ก5 / ก 6. +V!' &$K2%#2&#'ก ,ก*C()*ก* *+ B!7'# 99D./,I/+' 1 &$K2%#2 6 ?# 6: +&$K2%#2 X2 ก O/G/7./6: +&$K2%#2 3%8:D&$K2%#29D,ก*CLCM, Y4L.8,G8 ก$2 3:D./I:$'' 2ก D%SM2%8 'ก$2 &$K2%#2G/7 ,ก*C5M G/7;SC 9DV?#48 ,(12&$K2%$C;*2#$% ก ,ก*C()*ก* *+ I:$'' 2ก D%SM2&#'&$K2%#2G/7,ก*C5M G/7;SC -?#I:$'' 2ก D%SM2&#'()*ก* *+ ;W 6 $Zกl#$% , Y4 9DI*9 O 9 ก9W 242#2SN -G/7#+T8X2&$K2%#2G/75M G/7;SC ,582 A + 2B → AB2 ()*ก* *+ # 99D,ก*CLCM6: +3ZZ C$'2/K 1. A + 2B → AB2 ,ก*C()*ก* *+ &$K2%#2,C/+4 ./I:$'' 2ก D%SM2-8 ,C/+4 กl#$% , Y4 R = k[A][B]2 ก r3;C'ก CW ,2*2L(&#'()*ก* *+ 9D,(12C$'2/K (;.Z$%*,(12( D,NG- +-4 . M#2)
230
RATE OF CHEMICAL REACTION
2552
2.
A + B → AB ,ก*C5M AB + B → AB2 ,ก*C, Y4 ,ก*C()*ก* *+ &$K2+8#+ 2 &$K2%#2 mC+&$K2%#23 ก,ก*C5M &$K2G/7 2 ,ก*C, Y4 I:$'' 2ก D%SM29D./ 2 -8 ,2?7#'9 ก&$K23 ก,ก*C5M 9!'X5M,(12&$K2%$C;*2#$% ก ,ก*C()*ก* *+ I:$'' 2ก D%SM2&#'&$K22/K9D V?#48 ,(12I:$'' 2ก D%SM2&#'()*ก* *+ ,2?7#'9 กX2&$K2G/7,ก*C5M ,ก/7+4&M#'ก$Z#2SN - A 3:D B #+8 ':D 1 #2SN ∴ กl#$% , Y4 R = k[A][B] ก CW ,2*2L(&#'()*ก* *+ 9D,(12C$'2/K 6 8.10 E a 3:D E a ,(12I:$'' 2ก D%SM2 1 2 &#'&$2K 1 3:D 2 % .:W C$Z 3:D ,(12I:$'' 2ก D%S2M &#'()*ก* *+ ,I D,(12I:$'' 2ก D%S2M &#'&$2K G/7,ก*C5M
6.6
D95 / U1 46 . ก ก ก
mC+G$74FL( m.,:กS:;842X6 89D./I:$'' 22M#+ก48 Ea ,.?7#,I*7.#SO6NT.*X6M3ก8 DZZ9DGW X6M./m.,:กS:I:$'' 2;T'F,I*7.&!K2 m.,:กS:G/7./I:$'' 2;T',6:8 2$K2;84262!7'9D./I:$'' 2. กก48 Ea B!7'VM ,&M . 52ก$2X2G* G 'G/7,6. D;.กY9D,I*7.#$% ก ,ก*C()*ก* *+ LCM :$ก"OD&#'ก r3;C'ก ก D9 +I:$'' 29:2<&#'m.,:กS: ,.?7##SO6NT.*,I*7.&!K29D,(12 C$'2/K
6 6.11 ก @<; /ก ก 3: T9 // :9 a5 /Z 9กU9 1 U 46 . /ก
E = I:$'' 2,q:/7+&#'m.,:กS:G/7 T1 B!7'./-8 2M#+ก48 Ea 231
RATE OF CHEMICAL REACTION
2552
G/7 T1 9W 242m.,:กS:G/7./I:$'' 2. กก48 Ea 9D./9W 2422M#+ (-?#;842 X2ก r) 3:DG/7 T2 9W 242m.,:กS:G/7./I:$'' 2. กก48 Ea 9D. กก48 (-?#;842 3:D X2ก r) 9D,6Y2LCM48 Ea ./-8 -'G/7 L.8&!K2ก$Z#SO6NT.* ; U D95 / U1 46 ก. ก ,I*7.#SO6NT.* GW X6M9W 242m.,:กS:G/7./I:$'' 2;T'F ,I*7.. ก&!K2 ,.?7#52ก$29!',(12 ,6%SX6M()*ก* *+ ,ก*C, Y4&!K2 &. ก ,I*7.6 ?#:C#SO6NT.* 9DL.8GW X6M-8 Ea ,(:/7+23(:'L( -. #SO6NT.*2#ก9 ก9DGW X6M()*ก* *+ ,ก*C, Y4&!K23:M4 +$'; . V,(:/7+2ก:Lก&#'()*ก* *+ LCM '. mC+G$74FL( ,.?7##SO6NT.*,I*7.&!K2 10OC #$% ก ,ก*C()*ก* *+ 9D,I*7.( D. O 2-3 ,G8
6.7
D95 / , ./ ก . ก ก ก
%$4, 8'()*ก* *+ GW X6M()*ก* *+ ,ก*C, Y4&!K2LCM ,I DL(:CI:$'' 2ก D%SM2&#'()*ก* *+ %$4, 8'()*ก* *+ # 99D./;842 84.X2ก ,ก*C()*ก* *+ mC+% ' 6 ?# mC+G '#M#.กYLCM # 99D GW X6M,ก*Cก:Lก&#'()*ก* *+ 3ZZX6.8G/7./6: +&$K2%#2LCM ,582 ()*ก* *+ A → B ก. VM %$4, 8'()*ก* *+ ./;842 84.X2ก ,ก*C()*ก* *+ mC+#M#. ,582 584+9$CG* G 'ก 52X6M ,6. D;. X2ก O/2/Kก:Lก&#'()*ก* *+ 9D,6.?#2,C*. ,I/+'3%8I:$'' 2ก D%SM2:C:',G8 2$K2 &. VM %$4, 8'()*ก* *+ ./;842 84.X2ก ,ก*C()*ก* *+ mC+% ' 9D,ก*Cก:Lก&#'()*ก* *+ 3ZZ X6.8 ,582 A + X → AX ,ก*C5M AX → B + X ,ก*C, Y4 X
A→ B %$4, 8'()*ก* *+ (X) 9DGW X6M,ก*Cก:Lก&#'()*ก* *+ ,(12 2 &$K2%#2 X2ก O/2/K &$K23 ก,ก*C5M &$K2G/7 2 ,ก*C, Y4 Ea &#'&$K23 ก9D. กก48 &$K2G/7 2 Ea &#'G$K' 2 &$K2 9D./-8 2M#+ก48 Ea ,.?7#L.8X5M%$4, 8'()*ก* *+ :$ก"ODก r,.?7#X5M%$4, 8'()*ก* *+ ,( /+Z,G/+Z9 ก,.?7#L.8X5M 9D,(12C$'2/K
232
RATE OF CHEMICAL REACTION
2552
6 6.12 ก , ./ ก T /< .9 . T9 // ก 3 U < .[ .[ 9 < 9/ก9[ก5 / ก
Ea , Ea % .:W C$Z
-?#I:$'' 2ก D%SM2&#'()*ก* *+ G/7L.8./%$4, 8'()*ก* *+ 3:D./%$4, 8'()*ก* *+
9D,6Y2LCM48 Ea > Ea 3:D ∆E L.8,(:/7+2 3(:' ; S(LCM48 ()*ก* *+ ,ก*C, Y4&!K2 ,I D I:$'' 2ก D%SM2:C:' 3%8I:$'' 2&#'()*ก* *+ (∆E ) ,G8 ,C*. ,I D%$4, 8'()*ก* *+ :C,qI D I:$'' 2ก D%SM2,G8 2$K2 L.8,ก/7+4ก$ZI:$'' 2&#'()*ก* *+
6 6.12 5 , ./ ก 9 ก9[ก5 / ก 0 7 T9 // ก 3 U 9 9/
E a > E 'a 1 3:D E a > E 'a 2 3;C'48 I:$'' 2ก D%SM2:C:'
E 'a1 > E 'a 2 3;C'48 &$K23 ก,(12&$K2%$C;*2#$% ก ,ก*C()*ก* *+
3:DV?#48 E 'a1
-?#I:$'' 2ก D%SM2&#'()*ก* *+ G/7./%$4, 8'()*ก* *+
) ก ก. %$4, 8'()*ก* *+ GW X6MI:$'' 2ก D%SM2:C:' ()*ก* *+ 9!',ก*C, Y4&!K2 &. %$4, 8'()*ก* *+ L.8./J:%8#I:$'' 2&#'()*ก* *+ -. VM ,(12()*ก* *+ G/7J$2ก:$ZLCM %$4, 8'()*ก* *+ 9D:CI:$'' 2ก D%SM2G$K'()*ก* *+ L(&M '62M 3:D+M#2ก:$Z
233
RATE OF CHEMICAL REACTION
6.8
2552
ก 0 / 5 / , ./ ก *= D; X2ก O/G/7%$4, 8'()*ก* *+ ./;V 2D%8 '9 ก; %$K'%M2 ,582 X5M Pt ,(12%$4, 8'()*ก* *+ X2 Pt
C2H 4 + H 2 → C2 H 6 ()*ก* *+ 9D,ก*C&!K2G/7J*4&#' Pt mC+ Pt 9D 4.ก$Z H ,(12 PtH 3:M49!'L( 4.ก$Z C2H4 LCM ,(12 C2H6 2Pt + H 2 → 2PtH 2PtH + C 2 H 4 → 2Pt + C 2 H 6 Pt
C2H 4 + H 2 → C2 H 6 X2()*ก* *+ C$'ก:8 4 +*7'%$4, 8'()*ก* *+ ./I?K2G/7J*4. ก,G8 XC กY9D+*7',ก*C()*ก* *+ LCM, Y4 ,G8 2$K2 , . / 6.10 ; A GW (l*ก* *+ ก$Z; B LCM; C B!7'./ก r3;C'ก CW ,2*2L(&#'()*ก* *+ C$'2/K
ก. I:$'' 2ก D%SM2&#'()*ก* *+ -?#-8 I:$'' 2584'XC (PQ , QR , PR , PS) &. VM X;8%$4, 8'()*ก* *+ :'L( ก r3%8:D;8429D./ก ,(:/7+23(:'#+8 'L
ก. 9 กกก r I:$'' 2ก D%SM2&#'()*ก* *+ -?# PQ &. %$4, 8'()*ก* *+ :CI:$'' 2ก D%SM2 3%8L.8:CI:$'' 2&#'()*ก* *+ C$'2$K2 9SC P 9D:C%7W :' 9SC X 3:D Y 9D-'G/7 , . / 6.11 VM ก r D648 'I:$'' 23:Dก CW ,2*2L(&#'()*ก* *+ (ก) , (&) ,(12L(C$'3;C'
234
RATE OF CHEMICAL REACTION
2552
&M#-4 .,ก/7+4ก$Z()*ก* *+ G$K';#'2/K &M#XCJ*C 1. ()*ก* *+ (ก) ,(12()*ก* *+ - +-4 . M#2 ;842 (&) CTC-4 . M#2 2. I:$'' 2ก D%SM2&#' (ก) 9D,(12- !7'62!7'&#'I:$'' 2ก D%SM2&#' (&) 3. J:*%N$OP<G/7LCM9 ก (ก) 9D,;V/+ ก48 J:*%N$OP<G/7LCM9 ก (&) 4. ก rG$K';#'L.8X6M&M#.T:,ก/7+4ก$Z#$% &#'()*ก* *+ ,:+ (1) VTก%M#' (ก) ,(12()*ก* *+ - +-4 . M#2 ,I DJ:*%N$OP<./I:$'' 2%7W ก48 ; %$K'%M2 ;842 (&) ,(12()*ก* *+ CTC-4 . M#2 ,I DJ:*%N$OP<./I:$'' 2;T'ก48 ; %$K'%M2 (2) VTก%M#' Ea &#' (ก) = 100 - 60 = 40 kJ/mol Ea &#' (&) = 100 - 20 = 80 kJ/mol ∴ Ea &#' (ก) ,(12- !7'62!7'&#' (&) (3) VTก%M#' ,I DJ:*%N$OP<X2 (ก) ./I:$'' 2%7W ก48 X2 (&) 9!',;V/+ ก48 (4) J*C ,2?7#'9 ก Ea ,(12&M#.T:G/7X5MกW 62C#$% ก ,ก*C()*ก* *+ LCM ()*ก* *+ G/7./ Ea 2M#+ (ก) 9D,ก*CLCM, Y4ก48 G/7./ Ea . ก (&) < cdก 6.1 1. X2()*ก* *+ A → B → C ./ก ,(:/7+23(:'I:$'' 2C$'2/K
235
RATE OF CHEMICAL REACTION
ก. &. -. '.
2.
2552
&M#-4 .%8#L(2/K &M#-4 .XCVTก%M#' ,ก*C()*ก* *+ 2 &$K2 3:D,ก*C; B &!K2. กI#Fก$Z; C ()*ก* *+ A → B ,ก*CLCM, Y4 ()*ก* *+ B → C ,ก*CLCM5M ,ก*C()*ก* *+ 2 &$K2 3%8; B ก: +,(12; C 926.C J:*%N$OP<;SCGM + -?#; B 52*C,C/+4
; A GW ()*ก* *+ ก$Z; B LCM; C 3:D ; D VM ./%$4-D%DL:;<9DGW X6M,ก*C()*ก* *+ , Y4&!K2
ก. I:$'' 2ก D%SM2L(&M '62M &#'()*ก* *+ G/7./%$4, 8'()*ก* *+ -?##DL &. I:$'' 2ก D%SM2&#'()*ก* *+ +M#2ก:$ZG/7L.8./%$4, 8'()*ก* *+ -?##DL -. ,.?7#./%$4, 8'()*ก* *+ ; . V:CI:$'' 2ก D%SM2LCM,G8 XC 3. ก. &. -. '.
,.?7##SO6NT.*,I*7.&!K2#$% ก ,ก*C()*ก* *+ ,I*7.&!K2CM4+ ,6%SJ:&M#XCVTก%M#'G/7;SC 9W 242m.,:กS:G/7./I:$'' 2;T'ก48 I:$'' 2ก D%SM2,I*7.. ก&!K2 m.,:กS:G/7./I:$'' 2;T'ก48 I:$'' 2ก D%SM252ก$2. ก&!K2 9W 242m.,:กS:G/7./I:$'' 2;T'ก48 I:$'' 2ก D%SM2,I*7.. ก&!K2 3:D./ก 52ก$2. ก&!K2 m.,:กS:G$K'6.C&#'; %$K'%M2./I:$'' 2;T'ก48 I:$'' 2ก D%SM23:D52ก$2. ก&!K2#+8 'VTก G* G '
236
RATE OF CHEMICAL REACTION
4.
2552
()*ก* *+ 2A + B → A2B 9 กก !ก" IZ48 ./กl#$% , Y4 C$'2/K R = k[A]2 9',&/+2ก:Lก&#'ก ,ก*C()*ก* *+
5.
()*ก* *+ A + B → C ./J:ก GC:#'C$'2/K -4 .,&M.&M2 (m.:/:*% ) #$% , Y4&#'()*ก* *+ ก GC:#'G/7 (m.:/:*% -4*2 G/) A B 1 0.010 0.010 2.0 2 0.010 0.020 4.0 3 0.030 0.020 12.0 ก. VM กW 62CX6M r = #$% , Y4&#'()*ก* *+ , k = -8 -'G/7 , [A] = -4 .,&M.&M2 &#' A , [B] = -4 .,&M.&M2&#' B #$% , Y4&#'()*ก* *+ 2/K,&/+2LCM,(12#+8 'L &. -8 -'G/7 k &#'()*ก* *+ ,(12,G8 XC (6284+ :*% /m.:-4*2 G/) 6. X2()*ก* *+ Mg (s) + 2HCl (aq) → MgCl2 (aq) + H2 (g) IZ48 ,.?7#Xก:M()*ก* *+ 9D ;*K2;SC2$K2 #$% ก ,ก*C3กf;LumC ,929D:C:' G$K'2/K,I D,6%SXC 7.
3rก,%# <G/7./#*GH*I:%8##$% ก ,ก*C()*ก* *+ ,-./ -?# ก. -4 .,&M.&M2&#'; :D: + -4 .C$2 %$4-D%D:*;%< I$2HDm-,4,:2%< &. I$2HDm-,4,:2%< #SO6NT.* -4 .,&M.&M2&#'; :D: + -4 .C$2 -. #SO6NT.* -4 .,&M.&M2&#'; :D: + I?K2G/7J*4 %$4-D%D:*;%< '. #SO6NT.* I$2HDm-,4,:2%< I?K2G/7J*4 %$4-D%D:*;%<
8.
; C 3:D; D ,(12J:*%N$OP<G/7LCM9 กก J;.; A 3:D B ,&M CM4+ก$2 ก r3;C'ก ,(:/7+23(:'-4 .,&M.&M2&#'; A , B , C 3:D D ,.?7#()*ก* *+ CW ,2*2L(,&/+2LCMC$'2/K
9 กก r 9'; S(J:G/7,ก*C&!K2
237
RATE OF CHEMICAL REACTION 9.
2552
,.?7#2W 3J82m:6D3.ก2/,B/+. (Mg) . GW ()*ก* *+ ก$Zก CLumC -:# *ก (HCl) 9DLCM3กf; LumC ,92 (H2) ,ก*C&!K2 VM 9$Z,4: 3:D4$C( *. % &#'3กf; 9DLCMJ:% .ก r
ก. ก r584'XCG/73;C'48 3กf;LumC ,92,ก*C&!K2X2#$% G/7 4C, Y4. กG/7;SC &. VM X5M3J82m:6D3.ก2/,B/+../&2 CX6 8&!K2 ก rG/7LCM9D./:$ก"OD#+8 'L -. ,.?7#(:8#+X6M,ก*C()*ก* *+ L(, ?7#+F 923.ก2/,B/+.VTกX5ML(X2()*ก* *+ 6.CL( VM 2W ,# .4:&#'3.ก2/,B/+.. ,&/+2ก r;$.I$2H<ก$Z,4: 9DLCMก r./ T(:$ก"OD#+8 'L
238