Anorganik kimyo
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- Bu sahifa navigatsiya:
- = ([/2 + pK2) - ( f / l + i pFi);
- Modda ДН°а98 kJ/mol Modda ДН°Г2911 kJ/mol Al(g) 326,3 H20 ( s )
- K+(s) -2 5 1 ,2 A12(S 0 4)3 -3442,2 KCl(q) -4 3 5 ,9 C(olmos)
- CO(g) -1 1 0 ,5 KOH(q) -4 2 5 ,8
- 121,3 Na (g) 108,3
- H+(g) 1536,2 Na2S 0 4 (q) -1 3 8 4 ,6 H*(s) 0 O(g) 246,8
- 230,2 HF (g) -2 8 8 ,6 S (monoklinik) 0,30 HI(g) 25,9
- -1 7 4 ,1 S 0 3(s) -4 3 9 ,0 H2o (g ) -2 4 1 ,0 ZnO(q) -3 5 0 ,8
- S reaksiya
дН] = дн2 + дн3. Tajribalar jarayonida ДН, va ДН 2 ju d a oson aniqlanishi m um kin. Д Н 3 esa G ess q o n u n i asosida hisoblab topiladi: ДН 3 = д Н | - Д Н 2 = -3 9 6 ,0 -(1 1 0 ,5 ) = -285,5. R eaksiyaning issiqlik effekti sistem a ichki energiyasi va e n ta l- piyasi o 'z g a rish i n atijasid ir. S istem an in g ichk i energiyasi un in g b a rc h a en ergiy alari y ig 'in d isi b o 'lib , u n g a m o d d a n i tashkil etg an a to m va m o lek u lalarn in g ilg arilan m a, ay lan m a h arak atlari h a m d a y adro va e le k tro n la m in g enei^giyalari va h o k a z o b arc h a energiyalar kiradi. Ich ki e n e rg iy an in g m u tla q q iy m a tin i o ‘lch a b b o 'lm a y d i, faq a t u n in g o 'z g a rish i (Д U) ni o 'lc h a s h m u m k in . T e rm o d in a m ik a n in g I q o n u n ig a m u v o fiq siste m a n in g ichk i energiyasi a tro f-m u h it b ila n issiqlik alm a sh in u v i b o 'lg u n ig a q a d a r o 'z g a rm a s b o 'lad i. A gar sistem ag a ta sh q a rid a n q o 's h im c h a issiqlik energiyasi ( Q) berilsa, sistem a b ir h o latd a n ik k in ch i h olatga o 'ta d i. Y utilgan issiqlik m iq d o ri sistem a ichki en erg iy asin in g o 'z g a rish ig a va tashqi kuchlaiga qarshi bajarilgan ishning yig'indisiga teng bo'ladi:
B ajarilgan ish esa, siste m a b o sim i d o im iy lig id a: p = const; A = pA V = p(V2 - Fj); Qp = AU + p(V2 - K,) = U2 - U, + p(V2 - K,) = = ([/2 + pK2) - ( f / l + i pFi); = H l - U2 + P V2 = H 2; Qp = H 2 - H ^ A H H = U + p V ; A H = AU + p A V A H — k a tta lik e n ta lp iy a deb atalad i. E n ta lp iy a n i keng ay g an siste m a n in g en erg iy asi d ey ish m u m k in . O 'z g a rm a s b o s im d a b o rad ig a n kim yoviy reaksiy an in g issiqlik effekti sistem a en ta lp iy a sin in g o 'zg arish ig a teng. O 'z g a rm a s h a jm d a b o rad ig a n ja ra y o n la r u c h u n jism g a b e rila- d ig an issiqlik m iq d o ri u n in g ichki en erg iy asin i o 'z g a ris h ig a (AU) s a rf b o 'lad i:
Y u q o rid a g ila r aso sid a quyidagi xu lo sag a kelish m u m k in : Qp ~Q v = P&V D o im iy b o sim va h a jm d a g i issiqlik effektlari ay irm asi s h u g a z n in g k en gayish ish ig a teng. A g ar b u k a tta lik n i M en d eley ev — K layp eron ten g lam asiga qo'yilsa: p A V = A nR T hosil b o 'la d i. B u n d a An — reaksiyada ish tiro k etay o tg an g a z sim o n m o d d ala rn in g m o l m iq d o rlarin in g o 'zg arish i. A g ar sh u te n g la m a n i iz o b a r v a iz o x o r issiqlik effektlari farqiga b o g 'la n sa : Qp - Q y = A n R T ; A H = A U + A n R T A g a r n = 0, b o ‘lsa A f f = U. A g a r k im y o v iy ja r a y o n d a q a ttiq va su y u q m o d d a la r is h tiro k e ts a A n ni h is o b la s h d a u la r e ’tib o rg a o lin m a y d i. K im y o v iy ja ra y o n J a rd a m o d d a m iq d o r in in g o 'z g a r is h so n i (A n) s te x e o m e tr ik k o e ffits iy e n tla r o ‘z g a ris h ig a te n g lig in i h i so b g a o lish kerak . M a s a la n , su y u q s u v n in g h o sil b o 'lis h issiq lik e ffe k tin i h i so b lan g . 2 9 8 К d a j a r a y o n n i n g 0 ‘z g a r m a s h a jm d a g i is s iq lik e ffe k ti — 2 8 4 ,2 k J / m o l g a te n g . 2H 2(g) + 0 2(g )= 2 H 20 (s)+ 5 7 1 ,6 k J ^ ~ ^ ^ m a h su lo tla r ~ ^ ^
d a s tla b k i m o d d a la r — 0 — 3 — —3. B u q iy m a tn i q u y id a g i te n g la m a g a q o ‘y a m iz :
= - 2 8 4 , 2 - 7 , 4 = -2 91,6 — . mol E k z o te rm ik ja ra y o n la rd a s is te m a n in g ich k i en erg iy asi va e n ta l- p iy a si k a m a y a d i, s h u sa b a b li: A U < 0; A H < 0. E n d o te rm ik ja ra y o n la rd a esa siste m an in g ichki energiyasi o rta d i, s h u sa b a b li: A U > 0; A H > 0 bo'ladi. 4 . 2 .T e n n o k i m y o v i y h i s o b l a s h l a r T e r m o k im y o v iy h is o b la s h la rd a m o d d a la r n in g s ta n d a r t h o sil b o 'lis h issiq lig i (e n ta lp iy a s i) tu s h u n c h a s i q o 'lla n ila d i. S ta n d a r t s h a r o itd a 1 m o l m u ra k k a b m o d d a n in g o d d iy m o d d a la r d a n h o s il b o 'lis h id a g i re a k siy a sin in g issiq lik effekti s h u m o d d a n in g s ta n d a r t h o sil b o 'lis h issiqligi ( A № f,9g) d ey ilad i. B u y e rd a / — in gliz tilid a g i « fo rm a tio n » — h o s il b o 'li s h ( о б р а з о в а н и е ) m a ’n o s in i b e ra d i. B u n d a m o d d a n in g ag re g a t h o la tin i k o 'rsa tis h za ru r. O d d iy m o d d a - la m in g s t a n d a r t h o sil b o 'lis h e n ta lp iy a la ri (g a z s im o n k is lo ro d , su y u q b ro m , io d k ris ta lla ri, ro m b ik o ltin g u g u rt, g ra fit b a b o s h q a o d d iy m o d d a la r ) n o lg a te n g . B a ’zi m o d d a la r n in g h o sil b o 'lis h issiqliklari 9 -jad v a Id a keltirilgan. 9 - ja d v a l B a ’zi m oddalarning s ta n d a rt hosil b o ‘lish entalpiyalari (AH°f 2M) qiym ati
co2(g)
-3 9 3 ,5 M gS 04(q) -1 3 0 1 ,4 C aC 03(q) -1206,9 M gS 04*7H20 (q ) -3 3 8 4 CaClj(q) -7 9 6 ,3 N(g) 472,7 CaF 2(q) -1220,5 NO(g)
90,25 CaO(q) -6 3 5 ,5 N 0 2(g) 33 Ca(OH)2 -9 8 6 ,8 N O ,-(s) -2 0 7 ,5 Cl(g) 121,3 Na (g) 108,3 ci-(g)
-2 3 3 ,6 N a+ (g) 606,1 Cl-(s) -1 6 7 ,2 NaCl (q) -4 1 1 ,1 H(g) 217,98 NaOH (q) -4 2 5 ,6 H+(g) 1536,2 Na2S 0 4 (q) -1 3 8 4 ,6 H*(s) 0 O(g) 246,8 HBr (g) -3 5 ,9 8 0 3 (g) 142,3 HCI (g) - 9 2 ,3 O H - ( s ) 230,2 HF (g) -2 8 8 ,6 S (monoklinik) 0,30 HI(g) 25,9 SO ,(g) -2 9 6 ,9 N H ,(g) -4 6 ,1 9 S 0 3 (g) -3 9 6 ,1 H NO j(s) -1 7 4 ,1 S 0 3(s) -4 3 9 ,0 H2o (g ) -2 4 1 ,0 ZnO(q) -3 5 0 ,8 M a s a la n : H 2( g ) + i o 2(g )= H 20 (s)+ 2 8 5 ,8 k J H 2( g ) + ^ 0 2(g )= H 20 (g)+ 241,()kJ
Y u q o rid a t a ’rifi k eltirilg an G e ss q o n u n id a n q u y id a g i x u lo sa la r kelib c h iq a d i: 1 ) re a k s iy a n in g issiq lik effek ti re a k s iy a m a h s u lo tla r i h o sil b o ‘lis h is s iq lik la ri y ig ‘in d is id a n d a s tla b k i m o d d a la r n in g h o s il b o ‘lish issiq lik la ri y ig ‘in d is in in g a y irm a sig a ten g : aA + bB = c C + dD A H r e a k s iy a = X
Д Я ° / , 2 9 8 d o s t .m o d d a la r
lish issiq lik la ri y ig ‘in d isi; ХД H ° ( m dM moddalar - s ta n d a r t s h a r o itd a d astlabki m o d d a la rn in g h o sil b o 'lis h issiqliklari yig‘in disi. A # ° reaksya — s ta n d a r t s h a r o itd a k im y o v iy re a k siy a n in g issiq lik effekti. M iso l: A l 2 0 3 (k) + 3 S 0 3 (g) = Al 2 ( S 0
4 ) 3 (k) R e a k s iy a n in g issiq lik e ffe k tin i h iso b la n g : ДН°Г298 Al20 3(k) = —1675,1 kJ/m ol; ДН°Г298 S 0 3 gaz = —396,1 k J/m ol; ДН°Г298 A12( S 0 4)3 = — 3434,0 kJ/m ol ДН°гсак5>а = ( Д Н ; 2И A12( S 0 4)3)—( д н ° Г29а a i 2 o 3+ з д н ° г298 s o 3)= —3434—[—1675,1 + 3(—396,1)] = - 5 7 0 ,6 kJ/m ol 2) K im y o v iy re ak siy an in g issiqlik effekti re ak siy ag a k irish u v ch i m o d d a la r y o n is h issiq lik e ffek tlari y ig 'in d is id a n reak siy a m a h su lo tla ri y o n is h issiqlik effektlari y ig 'in d is in in g a y irm a sig a ten g . Y o n is h issiq lig i d e b (Д Н °с298) 1 m o l m o d d a n i m o ‘l k is lo ro d ishtirokida o d d iy o k sid larg ach a y o n ish id a ajra lad ig an issiqlik m iq d o ri tu s h u n ila d i. c - h arfi c o m b itio n — in g liz tilid a g i « y o n ish » s o ‘z in in g b o s h h arfi. Y u q o rid a g i t a ’rifga k o 'ra : A H rea ksiy a — ^ Д
H c,2 9 % d a si.m o d d a la r c .2 9 8 n w h su U u icr K islo ta v a a so s re ak siy ag a k irish ib , 1 m o l su v h o sil b o 'lis h id a ajralib c h iq q a n issiqlik m iq d o ri neytrallan ish issiqligi deyiladi. K u c h li k islo ta v a k u c h li a s o s la rn in g s u y u ltirilg a n e r itm a la r i re a k siy a g a k iris h g a n d a n e y tra lla n is h issiqligi s ta n d a r t s h a r o itd a o ‘z g a rm a s q iy m atg a ega: 2 N a 0 H (s )+ H 2S 0 4(s )= N a 2S 0 4(s)+ 2 H 20 (s ); AH °neytrallanish = 57,5 k J/m o l K o ‘p d a n - k o ‘p m o d d a la r n in g s ta n d a r t s h a ro itd a g i h o sil b o 'lis h v a y o n is h issiq lik lari ja d v a lla r d a b e r ilg a n b o 'la d i. S h u q iy m a tla r asosida ju d a k o 'p jara y o n lam in g issiqlik effektlarini hisob lash m u m k in . l ) e r is h ja ra y o n i: K O H (k )+ a q = K +(a q )+ O H ' (aq); -4 2 5 ,8 -2 5 1 ,2 -2 3 0 ,2 AH °eritm a= [(-251,2+ (—2 3 0 ,2 ) ] - ( —4 2 5 ,8 )= -5 5 ,6 k J/m o l - 2
N a(k) -> N a ; 0 108,5 (g) AH bugManish = 108,3 0 = 108, 3) Ik k i a to m li m o le k u la la m in g a to m la ig a p a r c h a la n ih ja ra y o n i u c h u n : A H ° d i s s o t sii = 2 1 0 5 ,3 - 0 = 210,6 kJ/m o l 4) V o d o ro d a to m in in g io n h o la tg a o 'tis h i d a io n la n ish ja ra y o n i u c h u n : H (g) -> H + e -; 217,98 1356,2
AH°ioniahish = 1 3 5 6 ,2 -2 1 7 ,9 8 = 1 3 1 8 ,2 2 kJ/m ol T e r m o k im y o v iy h is o b la r a s o s id a k im y o v iy b o g 'la r e n e rg iy a s i, k rista ll p a n ja r a e n e rg iy a s i,s u y u q la n is h , e ris h , g id ra ta ts iy a , m o le - k u la la r a ro t a ’s irla r, fa z a la r o 'z g a r is h id a g i v a b o s h q a h o la tla r d a g i issiq lik e ffe k tla rin i a n iq la s h m u m k in .
E n tro p iy a . M ik x o z a rra c h a la rg a b e ta r tib h a r a k a t x o sd ir. F a ra z q ilay lik , b irig a a z o t ik k in c h is ig a k is lo ro d t o ‘la tiIg a n ikki id is h b ir- biri b ila n tu ta sh tirilg a n b o ‘lsin. S h u id ish la m i tu ta sh tiru v c h i jo 'm r a k o c h ils a , g a z la r b ir-b iri b ila n a ra la s h a b o sh la y d i. A ra la sh is h a z o t va k is lo ro d ik k a la id is h d a b ir tek is ta q s im la n g u n c h a d a v o m e ta d i. Bu ja r a y o n h e c h q a n d a y e n e rg iy a o ‘z g a ris h is iz o 'z - o 'z i d a n s o d ir b o ‘la d i. L e k in te sk a ri ja r a y o n , y a ’n i g a z la rn in g q a y ta td a n k is lo ro d va a z o tg a a jra lish i o ‘z - o ‘z id a n s o d ir b o 'lm a y d i. C h u n k i g a z la r a ra la sh ib k e tg a n d a u la rn in g b e ta rtib lig i k a tta b o ‘lad i, ajra lg an h o la t esa ta rtib li h o la td ir. H a r q a n d a y s is te m a o 'z in i n g b e ta rtib lig in i o s h iris h g a in tila d i. T a rtib siz lik n in g m iq d o riy o 'lc h o v in i b e lg ila y d ig a n h o la t fu n k siy asi e n tr o p iy a d e y ila d i v a S b ila n b e lg ila n a d i. M o d d a n in g e n tro p iy a s i u n in g sh u h o la td a tu rish e h tim o llig in in g lo g arifm ig a to 'g 'r i p ro p o r - sio n a ld ir:
B u te n g la m a B o lsm a n te n g la m a s i d ey ilad i. к — B o lsm a n d o i- m iy si. W — s h u h o la tn in g e h tim o llig i. S is te m a b ir h o la td a n ik k in c h i h o la tg a o 'tg a n d a g i e n tr o p iy a o 'z g a rish in i o 'lc h a s h m u m k in . Iz o lirla n g an siste m a d a en tro p iy a n in g o 'z g a r is h i S q u y id ag i fo r m u la b ila n ifo d a la n a d i: c D
-holatdagi tartisizlik J — Д |^) 1
E n tr o p iy a n in g o 'lc h o v b irlig i — J /m o l- K . M o d d a q a ttiq h o la td a n su y u q h o la tg a , su y u q h o la td a n g az h o la tg a o 'tg a n d a u n in g e n tro p iy a si o rtad i. S iste m a e n tro p iy a sin in g o 'z g a ris h i issiqlik m iq d o ri o 'z g a ris h in i a b so lu t h a r o ra tg a n isb a tig a ten g d ir: bunda: AQ — issiqlik miqdori o'zgarishi; T — absolut harorat, K; entropiya birligi J/m ol-K . M is o l. 1 m o l m u z n in g e ris h id a e n tro p iy a o 'z g a ris h in i a n iq la n g . Q — m u z n in g e rish issiq lig i, 6 0 1 6 ,4 3 2 J / m o l; T = 2 7 3 ,1 5 A 5 = £ 0 - = 6 0 1 6 , 4 3 2 = 2 2 J / m o l K. T 273,15
S is te m a h a jm i o rts a , u n in g e n tro p iy a s i o rta d i. 1) C (grafit) + C 0 2 = 2CO IV 2V
Sj 2 ) N 2 + 3 H 2 = 2 N H 3 l v
3v 2v S is te m a n in g h a jm i k a m a y g a n d a , e n tro p iy a s i h a m k ic h ra y a d i: ДS < 0. 3)
A g a r re a k s iy a d a s is te m a n in g h a jm i o 'z g a r m a s a , u n in g e n tro p iy a s i h a m o 'z g a r m a y d i: H 2 + C l 2 = 2H C 1 l v l v
2 v А 5 '= 0 K im y o v iy ja ra y o n la rn in g o ‘z - o ‘z id a n s o d ir b o ‘lish ig a ikki n arsa ta ’sir qiladi. B irin c h id a n siste m a o ‘z in in g en erg iy asin i k am ay tirish g a in tilad i. Z a r r a c h a la r o ‘z a r o b irik ib y irik z a r r a c h a la r h o sil q ilis h g a in tila d i. C h u n k i k o ‘p b irik ish re a k siy a la ri e k z o te rm ik re a k siy a la rd ir: 2 H 2 (g) + 0 2 (g) = 2 H 20 (s ) + Q; (Д Н < 0 ) C aO (q) + H 20 (s ) = C a (O H )2 (q) + Q; (A H < 0 ) B u r e a k s iy a la r t o ‘g ‘ri y o 'n a l i s h d a b o r a d i, c h u n k i b u n d a s is te m a n in g e n ta lp iy a s i k a m a y a d i Д Н < 0. I k k in c h id a n y irik z a r r a c h a la r p a r c h a la n is h g a in tila d i, c h u n k i b u n d a u la rn in g e n tro p iy a s i o rta d i: 2 N H 3(g) = N 2(g) + 3 H 2(g) + Q; 2v
lv 3v K im y o v iy ja ra y o n u c h u n e n tro p iy a n in g o 'z g a rish i (Д5) s ta n d a rt s h a r o it d a m a h s u lo tla r a b s o lu t e n tro p iy a s i q iy m a ti y ig ‘in d is id a n s t a n d a r t s h a r o i t d a d a s tla b k i m o d d a l a r a b s o l u t e n t r o p i y a l a r i y ig ‘in d isin in g a y irm a sig a teng.
Д S reaksiya —
298 dasl .moddalar 'У ', ^ 298
mahsulotlar' B a ’zi m o d d a la r n in g s t a n d a r t e n tr o p iy a la r i (S °298) q iy m a ti 1 0 -ja d v a ld a keltirilgan. 10-jadval B a ’zi m oddalarning sta n d a rt en tro piyalari (S°298) qiymati M odda Co
M odda C° й 298 Modda CO Д 298 Ag(q) 42,55
Fe(q) 60,29
NaCl(q) 72,36
AgBr(q) 107,1
FeO(q) 60,75
N a2C 0 3(q) 136,4
AgCl(q) 96,07
G e(q) 31,1
O(g) 160,95
Agl(q) 115,5
H + (s) 0 02(g) 205,04 Al(q)
28,35 H2(g)
130,52 0 3(g)
238,8 B a C 0 3(q) 112 H N 0 3(s) 156,6 O H -(s)
-1 0 ,8 8 BaCl2(q)
126 N H 3(g)
192,6 P(oq)
41,1 Ba(N03)2(q) 214 H20 (g )
188,72 P(qizil)
22,8 B aS 04(q) 132 H20 (s )
70,08 Pb(q)
64,81 C(olmos)
2,36 H 20 ( q ) 39,33 S(g)
167,75 C(grafit) 5,74 H 2S 0 4(s) 156,9 S2(g)
228,08 CO(g)
197,54 KCl(q)
82,56 S,(g)
377 C 0 2(g)
213,68 K C103(q) 142,97 s,(g)
444,0 CH4(g)
186,19 K O H (q) 79,32 S 0 2(g)
248,1 CaCl2(q)
113,8 M gC 03(q) 65,7 S 0 3(s)
122 CaO(q)
39,7 MgO(q)
26,9 Sb(q)
45,69 C a C 0 3(q) 92,9 N 2(g)
199,9 Si(q)
18,82 Cl-(s)
56,54 N H 4N 0 3(q) 151 S i0 2(q) 42,09 Cl2(g)
222,9 N O(g)
210,6 S i0 2(shisha) 46,9 C r 0 3(q) 73,2 N 0 2(g)
140,2 Sn(q)
51,55 C r.O ^q ) 27,15 N 20 5(g) 355,7 ZnO(q)
43,64 M a s a la n : N 2(g) + 3H 2(g) = 2 N H 3(g) H a jm k a m a y g a n i u c h u n e n tr o p iy a k a m a y is h i k u z a tila d i: A S ° r = X S O N H 3
( S ° 2 9 S n 2 + 3 S ° 2 9 8 H 2 ) = = 2-(1 92,6)- [199,9+ 3(1309,52)] = - 2 0 6 ,2 6 J/g rad -m o l.
J a r a y o n d a h a jm o r t g a n i u c h u n h a n e n t r o p i y a o r tis h i y u z b e ra d i: AS°r= 2(197,54)—(5,74+213,68) = 175,66 J/grad-m ol A g a r ja r a y o n d a f a q a t q a ttiq m o d d a la r is h tiro k e ts a , e n t r o p iy a n in g o 'z g a ris h i n ih o y a td a k a m b o 'la d i. S u y u q m o d d a n i n g b u g ‘g a o 't is h i, k ristall m o d d a n in g e r is h i, q a ttiq m o d d a n in g s u y u q la n is h i k ab i ja ra y o n la rd a e n tro p iy a o rta d i. B u g 'n in g k o n d e n s a ts iy a la n is h i, s u y u q lik n in g k r is ta lla n is h i, h a jm k a m a y ish i b ila n s o d ir b o 'la d ig a n ja ra y o n la rd a e n tro p iy a k a m a y a d i. M asalan : H 20 (s ) = H 20 (g ) 70,08 188,72 AS°r .= 1 8 8 ,7 2 -7 0 ,0 8 = 114,64J /g ra d -m o l. Iz o b a r ik iz o te r m ik p o te n s ia l. H a r ik k a la o m iln in g re a k siy a y o 'n a lis h ig a t a ’s irin i o 'z i d a m u ja s s a m la s h tirg a n h o la t fu n k siy a si G ib b s energiyasi d eb a ta la d i v a G harfi b ila n belgilan adi. U en talp iy a v a e n tro p iy a b ila n q u y id a g ic h a b o g 'la n g a n :
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