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EQUTLIBRTUMn INUOLUTNG CHeMTCAL SYSTEmS 1
Pota ssium chloor decomposeo^ or^ heatirg
foam pota^ ssjum^ chloriode Oxygen
ku t 30,
ano
In thu n the produdt (^) Cannot combi ne to giue back potassium chloyae.^ In^ he^ case^ o cweible^ Hns the Ocvu (^) Onuy in^ ousavol decuoan^ These^ uns^ g to Complehon and mo (^) stosting maleials aue lt Howew he Huerible^ readian^ do^ not^ go^ to^ Comple^ tiom
hen hese Ans aHe^ peunumeol^ n^ closedcontoin^ es
a stage u. rcached at which thethe
top
nea diom appeas to.
though Some Stasuting makias^ au^ t
This statt Calltd Chemical^ equilibrium^.
Lets Consiolu a e Chemicaal tns un^ Ondento^ nde-
stand che^ mical^ eqitbrium
Decomposition 0t alcium^ Cabonáe^ When^ solid^ Calo,
sheakd in a closcol vessel at lo73k, dccompose
S oud,^ Calciwm^ Oxide^ and^ gaseoa^ CO.^ Du^ to^ the
b ddopeol^ in^ the with the help of a
into
01 CO,^ PutsSwHe
be
Produchon wul
NCSsed which COn recorded
manomeen As^ he.^ ompo^ siti^ on^ CalO^ (ontinus,
the pressuMe qoes on Inutasung. Aple Some ime it is Ob Sewol thot putsswu beComtaConstart at tontant tmp. evn though. Some CatO i shlpuestnt his Tmean that the amount_o CO produceol has be ceme ConstaniThu constanu PressuttL w that_ The
tqilbrium hasbeen eachcd Thismay be epren
as Ca Co (^) Ca0 (3)+ Colg ATE OF EqUTLTBRTUM The stake_in whith the
me asu4ablelepropetes the 34sttm do not undeug
an the notce able Chanqa undguen Aet o
Conduhon u said to be stat e equltb r*um
Attainment
an (^) ue
Httainment eauil ihuiun To LAnclenstont the meanung
o1 (^) Chtnicalequulibtium (^) consid a (^) simple (^) qernal
wusible rta cin Cauieol ina closed ues sel ata.
Constat tmpeuatuu A (^) lq) t (^) Blg) (^) Clg)t (^) Dlg)
At thestat^ of exp tht reoctanl A
and Bau present un duini Cont As thereaction
amongthe reactant
th
Proceeds he ledive (^) aelusicn moleules (^) result (^) in the (^) Jormaiutn th (^) produ
The tor uadreacion may be wr*ttn as
A +B (^) .Rn with he (^) possag (^) oime (^9) th conc of the^ neatanuodectase_while (^) those (^) ethe produprodud inoitasu^ Sinte^ theprodu (^) mo (^) ltculu aue nst
oullowtol to^ leaue the^ utud (Hn. u casitd oud tn the
ClosedContaint)thu ouo^ nea ct batk (^) amamg (^) themselu
to gloe back^ the rea ctanh. Ihebackwaud rn maybe
writlenas
This 1s betause the uate orma on o HIHA^ atat^ thethe
esult of thna
of HI.et the eqtdtbtum
euulibium become equa to the uat o lecomposition
heCon o tatahts and
AS POduct becomeConatant , Since both theopposung AnS..
Conhnue wen at he equwibiun has been reathed
3uwh a chemical tquullbrjum Rnouon as oynanmic
equilibrium
dhePropeis 0 the Systtm become constanl a elcbriun
Ound rumaun unchargid heea + g Jn the detompsi
tiem Ca CaCO evapoyation wa Un closed
us pressuubecome Constarnt at cquuubrium
(^3) he (^) eguiltbxium can (^) be (^) attoinec (^) ondyi tth (^) ssttm_u dosto one tor the stablish rment o esul thriumit i
quiteObuios hat^ the^ Sustm 3houldbe closeel
One (^) 9f (^) tht (^) 6yakm not (^) clos eol, (^) Some e (^) theProduds may C2Cope^ om^ he^ Containus^ and^ thet^ foue,^ the backwosud (^) Hh wl not (^) take (^) place (^) lonsesutntly, d
wuu not be possi ble attainhe euuibrimn
(^4) he (^) eguilibrium Can be approachedrom athu^ du
Equilbrlum Can be obtaine d hrom oth Sides
wheth we^ stait (^) the (^) Heaction (^) by (^) taking Halo) (^) andl Cg), and^ guHI (^) tg) o^ by taking (^) HIlQ)_whith Hg) and g).
aHI g)
ww decompose To Hlg)+ 9)
HI(g) (^) Ha(g+ (^) (g)
5 A (^) catolyst dosnot (^) akten (^) the (^) equiubrium (^) Point h a Hwuible rtachon, 0 Catalyst {ouwaud as well a backuwouol JAEQ ction to eq ual ex tnd
the
TheeocHt, t, thethe (^) tquilihxium
pout i^ nst allucd. Hottuyt
the cqillbrtumequlibritum^ memay be^ attained (^) canlic tn the (^) prtstntt el a catalat.
LAW OF MASS ACTToN
At OfOF MASSMASS (^) ACTTON (^) H (^) stakts that the^ Malt^ oa chemicalshemital Hhun sduurcty (^) proposctio nal to the (^) produ ct the kmp an gYon time
ma la toncz the actan at^ a^ corstont
he molaH Conc e mumbe o rnuls, pet
(ihe also^ Calleod actiut mass. 9+ s txpresSecd by
tncloSun AeSgmbols e 4anmulae e the substante
i quOHEbroCRA. tq melan Cone eo A tprtsstol
a5 LA.
Lt_ Consici ta simple sun bluw he Apecies A and B
A 8 B Produc
Acc to lauu^ maa adion,
Rati ertoction, X LAJLBJ K[AJLe whue LAJ and L8_asu the mola conc ethe reactaru Aard (^) Brespecively) I,e^ a^ a tonstant (^) e (^) propaselionauy fe heforuwaucd n Ond u knozon as rak canstant Iht Hate Conutort s also Called vdouty censtanit Nouw, the Con C tach ethe rcactan Unvolued i h 4eaction i uit A ALB) 1 then,
RadtuR o Reoction, kx 1x1 oM K
u be delined a th uof o the Hnthtn the Co nc
Thus constond^ H^ at^ a^ gwen^ temp
tath o he HeoctanD^ unih
nauie
Similah the batkuaxdtn
C+D (^) AEB Ral o batkwoud reacion LloJ.
Kteilaj
whut K the rate Constart (^) o thebatkuad req cion and Li DJ a mola Conc praclucls C 0 up
Atequiihrium, th rates twooP0pposung ms brcome.
equallheeoeat (^) eqil thriun, Rati el forwaud readm = (^) Rat o backwaud reacion k lA]Ca] lcl[b) Kb CA^ CB
The CombineoConstant K which is cqualto k is Calleo (^) cauil ibrium constant^ and has^ a^ constarl value (^) fon Mtacticn at qwen kmp The aboue eq Ls knoun as
lou oChemi cal egilibuium
tor (^) a qental Teaction (^) o (^) th ype
The
aA t bB cC+do
Theequltbium Constani ma befepresentd a K To
wheue heeXponenls 0,b and , O haue the samt vaiue as (^) those tn th (^) balanced (^) chemi (^) cal eguoi (^) on Thus, thene tquil ibrium Constant may be delined 2 The rao^ bluDthe (^) produd ef molou oftheproduc to the mslau Conc reactanl thtach. othucong tnm rajsedto a pouwe egual to
ConCs
ts Sti chio mibuc Ccelicieril in th balonted^ cherricai
quation at a Conitanl empoatuie
for example, for the reaction
9+ I, 19) H1 (
theqülibrium consta,kee^ ma
be wriUen a
Ke LHILoliq
Genualu the^ Subsoipt^ 'cg^ wed^ om^ expressing^ qu ium Contfhkrat on ù omitted. 9t u taken grand
that theConc, nthe expression tas Ke e egullbr
vau lhtuetot, wit
k [HILQl
In the about expressitn.,^ theCon^ the^ vauious^ 3pecaA He qenHal (^) eypr essed in kms o moletre SimilarySimilaxy the equilibrium ConstanI for he reoth on. yNH (q) t 50 lg) 4No (^) q) t^ 6H0 (^) lq)
K oHd
mo be notd that whilewuthng expression a eqillbriwn Conatant9ymbas o phase (S,J,g atLgnorcd unlus t u^ Uu essential. Equilibrium Constant aaco LA In gosto reaions the ConC gase may also be expres sed in. ouns 01 theis pauti al predlses
Sustms
be
for qaAcou
aA+bB cCt dD
We Can alsowrit P CRTas Lgal^ RT-Cii)
Now p CRI So tha PA LA] RT
hee TA] a themolau conoA Sinmilasuyp- PglB]RI_
Pa_[ RI
Po lo]RRI
whuu LA, L_and [DJ a the nala concg 8,Cand
D upectiuek
Substitutinq heae valuesinexpresion in Kp n Rg i.
Kp CA) R. (Ce) RT)b Tc lo RTd
CoJ RT)«
w.woa m
CRTCrd) (o6)
ke (RT)Cctd)-Ca+5)
Kp K, (RT)
wheuAn Ccrd)- latb) i:e
moles 6 mumber^ mo^ lea^ o
gastous produtA umbey 0O4t ousreatan un c
balanced chumical equation
tor Examplt
NH Cq)
KpKe CRI)An
And-((+3) -
Kp K CRT)*
inHalg) Talg) &HI Cq) An -(+) Kp = Kc (RI° KC
() dNou tg) (^) Nolq) lg)
AnEdtaJ
kp Kc (RI)=keR
Unibs o £quilibrium Contant The units Kwll depend uRon he no moles e tatont andpraducinuolueal un (^) thereaction s (^) diauu SEdahead UhJhun fotat no: molea oprodudh_i equal ta the. total mo e molu Q readand K hos no niaeg NaCg) 0, 19) ANo^ (q)
K NOa
1 the conç aut express ed tnteums molts peklutr t, mal
(molt ") (mol )
Simila for the reation
then no^ uniu
dHI (^) (9) (^) Hlg)Ja (^) 9)
K H LgLi ( molt)mol)^ no^ uni
THI (g) moll) *
06 (8-0xJ0 yx) om hatuKeethfolowingKe egulbuum, whn. the eguillbrim Conc e cach substante [sOo6oM o 08a^ M and^ LsD,3^ 1-9o^ m
Sol lhe^ Guili^ b^ rium^ Conatart ke -
Ke (^) Csa [so,3 Lo,3'
K 90 m) (o60M)"o 8a m
P PUg and Qu at_equilibaium. at oo
and (^) hainhawing Conc^ :59M PU, 157 M^ U^ and^ 4]m PUg Calculat^ ke^ aa^ thereoction. Pus Pu^ U Se The^ equilibriwm^ ConsiarT^ oth^ eacben^ ma be wut en a k Teuilu, CPus K L:52) -59)
79 M
Fnegui. Syskm^ fo^.^
rn: blw Hanol ta qwt HI
at 6To K na^ ire^ 4l08kConfain^ O4^ molt^ e^ H,
O4moleo1ano moles^ e^ Hr^ Calculat^ t Ea ibriuum on&tont gat : for the rea m, Ha (^) lg I, g)^ HI^ )
LH,CL
LD ola^ Con^ Co^ vouou_ápecic^ a^
equlLbriUm
[H3 b:9_0o8 mol L^7 o^
0 08_mo)L
CHI) (^5)
Subshe vauiou^ valuuin^ the^ abourexpressiOn^ fAAe
k _o:48)
(o.os)(oot)
36 o
Izcteuminko (^) to th reoction^ 2sQ^ g)tg)^ as_
Kp 3-4^ banat^ loooc
SeL Kp^ K^ (RT)^ O^ ke^ Kp^ LRD An -(a+l)=-
ke 3.^ 4x^ (o6^ 831373)'
-359: D coumin^ Kp^ athirea.ction No lg) 2 _àNO^ tg)^ t_Ulg
k 3 15 xlo^ l^ o69^ k_
Sell uWe^ kkp^ noo Kehat A i wbevaw An kp 3:75^ x^ Lo^ x(o*o^93 x^ lo69)
3:33 x1o
T Ja th cO
HeTogenous equilibniun : The equilibium eaction. in which (^) he (^) sueactant (^) and the (^) proolut (^) u preen tndilleaent phaseau caledhetuo genou eq uulbritum
Cacos ls) Cao (^) ls)+ (^) Co C
may be noted that the equlibiun
presslon oA hetuogenous ns doLs nothudi he
ConcCant (^) puesalio (^) becase theu (^) Conc, (^) rUmain Conston. (^) Similoar (^) the (^) Con c (^) Q (^) p iquials au also asumeol ta (^) be tonatart and hese dlo not Oppeaineguilibuium Cxpresi an. C-GCOnaide he httHagen.ouareacion- Cato,)
he CadL)t Co (^) lg
K (^) LCao (^) (LCo (^) a
LCa cO, s)
The (^) conC (^) of (^) aD (^) )and to Calo,^ (s)^ may^ be^ asumeol be (^) constasti.eCao (^) Co) and SO that k k lcolg)3 LCaco,s)J|
SInce the paual
LsPropautional (^) to (^) Concentrotian (^) kp_PCL This (^) ghows (^) that ata
presu a gaseU Cermpene
the paticua^ kmpel^ atun^ t^ fa deompogition (^) lalO the (^) equwibrium CO, podal PAeIsuAe yAtm is (^) equal (^) to (^) Kp.
Wsite he^ tquilibium ConstanT (^) expresions oUowu rn an^ th 5a Co s) Ba o('s)+Conl9)
K LBaA)lto.gJ
CBaCos
Set
By Convention, lBab(s)3 and lBaco, ls)=
ert
kLto, (g)J D kp plto)
Ag B ()
Sal!
Ag tag) tB (a9.)
k TAlaa) A las
Aq B
O kAg (ag)J Blaq Ag Bls) =||
CH CoCH ()
Spl
CHg Co CH, (9)
k lCH_ CocH lg
CCH Cot H% ()
oLCH, (oCH lg)
( TCH coCh () = 1]
CHy CHy (g 0, g) CO^ C9)t^ dHo^ l)
Soll
klcotg)1l'H,of] TCH 13 Ca
Co lg)
TCHyl9)3 log
AL (s) 3H laq) AL (aq)+_3 Ha g)
Sol
k AS Lag] [H,lg)Jo LAiag)l TAL&) [H laq)]
Als)=)
6 HPo (aq) + H,O Hs +^ Caq)+ Polas)
tor (^) arweuible..rh (^) heeailbriumLonstat an
the owauoL n: UnuuC he eguthrium
Constar_fouthebackuad utaction. e-9 1.equi ConstantKa hetn: combinatian b/u H
and I at 777k l
HIL9)
CHT] CH3CI Thenthe equi LonstanT_ (^) o (^) the (^) dlecomposib (^) an
HI k') he nueue he aboue equi: Cental
HI l9)
k HJlI)
CHT] K
T qeneLal KzOALUand rea chon
ba chwand s4ea cfon
The ualue an tquiLbsium Constan la he
xknd to which a n: puoctecds in he ouwad an
ThtTheequil (^) cbum (^) Conatant (^) isindepenolenl ehe
HvAt duection.
preaente catalyst Thu is becauuc the catolyAt olch heuaks eteuwa^d backu aral reactiom equall Application eEauilibuium Con4tant^1
he umtuital value e esulibrium
UmpaIart becouse hlps s
Rnou whethut weexptoL a An:miatuu oesuiltbri-.
Constant ia U
wm To Contain a high ox a low Conc oprodue This (^) inumationÚs U dulin
Imduustria procees becawethu hups to ptolutL whtth
enouh
PopOAto (^) industrial (^) procts (^) ike fo (^) max PHOdLct o^ not Chouh
Some o^ the^ imp appucau ons
equlibium Conu (^) tart (^) a
( T^ hupA topueolict the extenol me On tDE baay
of it magnitude
St e^ the n
hetps (^) calulate (^) equilibium, Conentratons
Pre (^) oliction (^) o (^) xtent of (^) Reaction 2lhe^ mogntuole equilibuium (^) Conatant (^) k (^) mdi (^) cate he extnol (^) to. whih
he (^) magntuoe o (^) the (^) equulibsium (^) conston and
a eatian Can g
In othe oHos u a meAHe
theComplttion e a HewONible_reachon Howev
u ma be notto thot an
an equibsiumn^ do^ not^ ive
Unoumation (^) abeut he (^) Hati at (^) whih (^) the
the
equjbuum U reahed Thus (^) faxg (^) tu the (^) value wu (^) be the Khe^ qrcae To equilibiium^ Conc^ of^ the^ produu^ TlotiuG those (^) he (^) reotanu
e rn Proceeo to a
qr eol^ ex^ Hnt O (^) K>lo, (^) producA predominaku Oue (^) Htatanls (^) aJ equil (^) thium (^) , ku^ ve (^) lauge the (^) n: neau o^ Comp (^) letiem procteo K< lo, Htoctan K (^) Uep (^) Bmal henn:proceeds to^ uey (^) im (^) a
predomimate (^) ou (^) produ (^) Y
exert0H (^) raruy unhe - Hange (^) et loto^ l0 (^) appe (^) dable Conc (^) o both (^) reactanKard (^) PHOduG (^) ou pusurt
ConC
Preoicing (^) the Dirrction (^) he (^) Reaction 1-» (^) The ind the^ equ
Constant aso hetps to di»" in whldh an
