MODIFICATION OF VANT HOFF PARAMETER FOR CONCENTRATE SALT SOLUTION

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1 VOL. 13, NO. 9, MAY 018 ISSN ARN Journl of Engineering nd Applied Sciences Asin Reserch ulishing Network (ARN). All rights reserved. MODIFICATION OF VANT HOFF ARAMETER FOR CONCENTRATE SALT SOLUTION Setiydi, Antresti Deprtment of Chemicl engineering, Widy Mndl Ctholic University Sury, Sury, Est Jv, Indonesi EMil: ABSTRACT Vn't Hoff eqution prmeters for clculting the oiling point rise elevtion is limited for dilute solution, the ojective of this reserch therefore ws to study the estimtion of Vn't Hoff prmeter for concentrted solution. Experiments were crried out using vrious slt which hs different vlence t vrious mollity. The result showed tht the prmeter vlues were influenced y strength of cidity or sicity of of the slt formed s well s the solution mollity. The slt formed from strong cid with strong se ffects the prmeter ut the slt formed from wek cid with wek se does not ffect the prmeter. The error level of eqution = + m / for ll type of slt t different mollity were insignificnce. The smllest error of slt is FeSO 4 5.7% nd the iggest of slt error is Al (SO 4 ) %. Keywords: oiling point rise, dilute solution, Vn't Hoff prmeter. INTRODUCTION Over the pst decde hs incresed the interest of lowslt melting point, including molten slt t room temperture, clled initilly room temperture of liquid slt or ionic liquid room temperture. This nme is grdully replced y the term ionic liquids or ionic room temperture. There is n incresing numer of pulictions of the synthesis report nd the nture of the low melting point slts. Reserch on the slt is prcticlly importnt, ecuse it is esy to hndle the liquid without providing extr het, which is necessry in the cse of clssicl high temperture liquid slts. Therefore they cn e used s non voltile solvents or electrolytes. (Gllus, 001). The multicomponent investigtion of the liquidsolid equilirium is quite importnt in chemistry nd in mterils science. Binry solidliquid phse digrms s the simplest representtives of these equiliri re determined in most physicl undergrdute chemistry courses s they provide wide vriety of thermodynmics nd informtion out the system (Nogueir, 011). Nonvoltile solute cuse decrese in the vpor pressure of solution so tht the vpor pressure of solution is lwys lower thn the vpor pressure of pure solvent, s result, the oiling temperture of the solution ecomes higher thn the oiling temperture of the solvent. The estimtion of oiling point elevtion cn e clculted using Vn t Hoff eqution. This eqution ws sed on the prmeters s function of mollity of the solution. But this prmeter is not suitle when used to clculte concentrted solution; therefore it is necessry reserch to produce prmeters in concentrted solution. To study the oiling point elevtion of concentrted solution n experiment ws conducted using electrolyte solution of vrious vlence of ions slt. The presence of dissolved sustnces (solutes) which re difficult to evporte cusing vpor pressure drops. The results otined y mny reserchers generlly indictes tht the oiling point of the solution in the form of dissolved solids in the liquid is lwys higher thn the oiling point of the solvent pure, this is due to the prticles of solute in solution locking the trnsfer of prticles of the solvent from the liquid phse to the gs phse so tht evportion of solvent prticles ecome ostructed (Bilik, 008). Colligtive properties of the solution do not depend on the interction etween the solvent nd solute molecules, ut depend on the mount of solute dissolved in queous solutions. At the sme concentrtion, the mount of prticles in non electrolyte solution is not equl to the mount of prticles in the electrolyte slt solution; ecuse electrolyte slt solution cn e decomposed into ions ut non electrolyte solution cnnot e decomposed into ions. rticles (toms, ions, molecules) of sustnce depend on intermoleculr forces cused y ttrction or repulsion of electric chrge etween molecules. Molecules in the liquid form cn overcome the force of other molecules. The composition of these molecules determines the physicl properties of liquids such s oiling point, freezing point, nd the surfce tension. This ehvior ffects the temperture nd pressure s well s contct with other sustnces, so it will lso ffect the rise in oiling point. (Lewndowski A., 010). The vlue of Vn't Hoff fctor is the numer of prticles of ions or molecules of dissolved slt solution. In ionic solution, prticles hve ttrction force so tht whenever positive ions nd negtive ions contcts will tend to stick together nd form ion pirs tht ct s single prticle. Therefore n ionic slt hving Vn't Hoff fctor greter thn 1 ecuse the Vn't Hoff fctor depends on the ion dissocition. The vlue of Vn't Hoff fctor is determined y experiment (Mron, 1975). MATERIAL AND METHOD Mteril The slts used re NCl (99.5% purity), CCl (98% purity), AlCl 3. 6H O (97% purity), N CO 3 (99.5% purity), FeSO 4.7H O (99.5% purity), Al (SO 4 ) 3.18H O (99.7% purity), N 3 O 4. 1H O (98% purity) nd C 3 (O 4 ) (99.3% purity), which purchsed from Kurni Jy Sury Indonesi. 3031

2 VOL. 13, NO. 9, MAY 018 ISSN ARN Journl of Engineering nd Applied Sciences Asin Reserch ulishing Network (ARN). All rights reserved. Theory The oiling temperture elevtion cn e clculted s eqution (1) ΔT = m. K.i (1) with ΔT s oiling point temperture elevtion, m is mollity solution nd K is oiling point elevtion mollity, nd i is the rtio of colligtive properties of electrolyte ginst non electrolyte solution. The i vlue ws determined experimentlly for ech type of electrolyte solution, once i hs een set then i lso pplies to the other colligtive properties. For the electrolyte solution the strength of tensile force etween the ions is stronger thn the prtil dissocition, so tht there is dditionl fctor g stting on colligtive properties eqution () when there is perfect ioniztion. i = ʋ. g () A quntittive pproch of the tensile force etween the ions is given y the DeyeHockel expressed s ionic strength (μ) nd is defined s n eqution (3). μ = 0.5. m. Z + + Z _ (3) for Z + is positive ions vlence nd Z negtive ions vlence. Ionic strength hve reltionship with the osmotic coefficient y the eqution (4). g 1 K. (Z. Z ). Then the comined eqution () nd (4), fctor i cn e expressed y the eqution (5). υ is the numer of moles of sustnce tht is ionized nd μ is the ionic strength, resulting in eqution (5) ioniztion influence fctors re included in the prmeter K, the eqution (5) cn e expressed s eqution (6). μ i.g (1 K. (Z. Z ). μ ) (4) (5) for is new prmeter tht cover the numer of ionized sustnce nd ionic strength. Then the comined eqution () nd (6), fctor T cn e expressed y the eqution (7). T m.k.i m.k.(1.(z. Z ) ) (Sukrdjo, 004) Vlue of prmeter is determined from dt of experiments in the form of prmeter is needed to solve prolems in engineering the eqution is intended s concise sttement to represent further implementtion of mthemticl opertions on the dt. Therefore empiricl equtions re ttempted in order to represent the dt s well s possile ut with simple form. The oiling point elevtion of the electrolyte solution therefore cn e expressed y the eqution (8) (13).m.m.m.e m. m m.. m. (7) (8) (9) (10) (11) (1) (13) METHOD The experiment ws conducted y dissolving NCl in totl of 100 ml of wter in eker glss. The solution ws heted up to oiling point. The sme method ws lso conducted for vrious type of slt solution tht hs difference vlence which were, CCl, AlCl 3, N CO 3, FeSO 4, Al 3 (SO 4 ), N 3 O 4, nd C 3 (O 4 ) The reserch ws conducted t vrious mollity, such s 0.5, 0.5, 0.75, 1.0, 1.5, 1.5, 1.75, nd.0 mol/kg. RESULTS AND DISCUSSIONS i 1.(Z. Z ). (6) Result 303

3 VOL. 13, NO. 9, MAY 018 ISSN ARN Journl of Engineering nd Applied Sciences Asin Reserch ulishing Network (ARN). All rights reserved. Boiling oint Rise, T ( o C) NCl CCl AlCl 3 N CO 3 FeSO 4 Al (SO 4 ) 3 N 3 O ,0 0,5 1,0 1,5,0,5 Mollity, m (mol slt/kg wter) Figure 1. The Reltionship etween Mollity with Boiling oint Rise Figure1 on for vrious vlence of ionic slt solution, the slt used is NCl, CCl, AlCl 3, N CO 3, FeSO 4, Al 3 (SO 4 ), N 3 O 4. The results otined in the form of the oiling temperture rise of the solution s function of the type of vlence slt nd slt mollity ws showed in Figure1. Then the oiling temperture difference etween the slt solutions with the pure solvent oiling temperture, expressed s the oiling point rise is used to clculte the prmeter using eqution (7). Furthermore, the vlue of prmeter ws used to clculte nd in eqution (8) to (13). The vlue of clcultion of nd nd corrected results ws showed in Tle1. Slt Tle1. rmeter vlue of nd nd error. Eqution of nd prmeters nd error Eq (8) c Eq (9) d Eq (10) f Eq (11) g Eq (1) h Eq (13) i NCL CCl AlCl N CO FeSO Al (SO 4) N 3O C 3(O 4) c : = +.m d : =.m f : =.e.m g : =. m h : = + m/ i : = m/( +.m)

4 VOL. 13, NO. 9, MAY 018 ISSN ARN Journl of Engineering nd Applied Sciences Asin Reserch ulishing Network (ARN). All rights reserved. Equtions (8) to (13) of Tle1 is mthemticl equtions of prmeter s vlence of positive ion nd vlence of negtive ion in slt nd mollity of slt solutions. All equtions of tle 1 show tht the equtions of = + /m hving smll error. For ll slt when is mde the eqution of prmeter in the = + /m then creted in grphicl is given in Figure. 8 6 rmeter 4 NCl CCl AlCl 3 N CO 3 FeSO 4 Al (SO 4 ) 3 0 N 3 O 4 C 3 (O 4 ) 4 0,0 0,5 1,0 1,5,0,5 3,0 Mollity, m (mol slt/kg wter) Figure. Reltionship etween Mollity with rmeter DISCUSSIONS The grph on Figure1 showed tht the greter the mollity of sline solution, the higher the oiling point elevtion of the slt solution. Figure1 lso showed tht solutions of NCl, CCl nd N CO 3 which were slt formed from strong cid with strong se hd oiling point greter thn other slt solution, since slt derived from strong cids nd ses strong ws esier to ionized nd my ionized perfectly. Figure1 showed tht high oiling point ws more influenced y the slt formed from strong cid with strong se while the vlence of ion whether positive or negtive slt hd less ovious effect, which ment tht the stronger the nture of the electrolyte in the slt, the higher the oiling point of the Figure1 lso showed tht solutions of NCl, CCl nd N CO 3 which were slt formed from strong cid with strong se hd oiling point greter thn other slt solution, since slt derived from strong cids nd ses strong ws esier to ionized nd my ionized perfectly. lt of these types formed y electrosttic forces nd the intermoleculr ionic strength which cuse the slt to hve reltively higher oiling point. Mens tht perfect ionizing slt hve lrge ionic strength nd hve greter oiling point (Wng X., 009). From Figure, prmeter is not linier to the slt mollity. Mens in the Figure the positive ion vlence nd negtive ion on the slt is not effect on the prmeter. The vlue of the prmeter more influenced y the type of slt from strong cid or wek cid with strong se or wek se, this is indicted y the vlue prmeter tht is not influenced y the positive ion vlence nd the negtive ion vlence of the slt. But in the Figure show tht solution with slt from strong nd strongly cidic cid hving lrge prmeter nd slt from wek cidic nd wek se hs smll prmeter, mening tht the ionized slt tend to the eqution of prmeter. Hs prmeter is lso determined y the strength of slt in decomposing the ions. Figure lso shows tht for the smll slt mollity, the vlue of prmeter is lso lrge, the prmeter is influenced y the strength of the slt in the ion while the mollity of the slt solution lrge is indictes the smll prmeter, mens for the evolution with slt content slt solution is more dificult to ionized mke slt molecules tht mke wter molecules to leve the liquid is smll, this is mkes the prmeter decresed, in the grph the prmeter tends to e constnt, mening for slt mollity is lrge vlue prmeters is fixed nd is not ffected y the slt mollity. For slt from comintion of wek cids nd wek ses, it tend to hve prmeter vlue tht cn e considered constnt, this is ecuse the slt in the form of comintion of wek cid nd wek se is hve ionizing strength nd the ttrction force etween molecules so tht it cn e sid tht only ionized slt hve lrge rmeter vlue nd the vlue prmeter is not chnges when the slt solution mollity lso is not chnges. Solution of strong slt to moleculr grvity cn mke slt solution hs high prmeter nd when the pull force etween molecules is wek hs low prmeter, so tht the oiling ility of liquid gretly ffects the prmeter. 3034

5 VOL. 13, NO. 9, MAY 018 ISSN ARN Journl of Engineering nd Applied Sciences Asin Reserch ulishing Network (ARN). All rights reserved. The mthemticl equtions showed constitute of prmeter s function of the positive ions nd negtive ions vlence of slt nd m, slt solution mollity. Of ll these equtions eqution formed from strong cid or wek cid with strong se or wek ses, this ws showed y the vlue of tht ws not only determined y the vlence positive ions nd negtive ions vlence of slt ut lso the type of slt. CONCLUSIONS The increse of the oiling point of the electrolyte slt solution is influenced y strong cid or wek cid nd strong se or wek se which form the dissolved slt. The increse of the oiling oint of the electrolyte slt solution is lso influenced y the price of the solution mollity. The slt prepred from strong cids nd strong ses when dissolved into wter solvent of prmeter vlues vries depending on the mollity of the slt solution prepred from the wek cid nd the wek se when dissolved into the wter solvent the prmeter vlue is considered. prmeter eqution tht hs the smllest corrected = + / m. The error level of eqution = + m / for ll type of slt t different mollity were insignificnce. The smllest error of slt is FeSO 4 5.7% nd the iggest of slt error is Al (SO4) %. REFERENCES Bilik M., Sedin. nd Thelinder H Boiling oint Rise Clcultions in Sodium Slt Solutions. Industril nd Engineering Chemistry Reserch. 47(4): Bird J Bsic Engineering Mthemtics, 5 th, p. 87, Royl Nvl School of Mrine Engineering, ortsmouth. Gllus J., Lin Q., Zumuhl A. nd Meister E.C Binry SolidLiquid hse Digrm Orgnic Compounds. Journl. Chemistry. Eduction. 78(7): 961. Ge X. nd Wng X Estimtion of Freezing oint Depression, Boiling oint Elevtion, nd Vporiztion Enthlpies of Electrolyte Solutions. Industril nd Engineering Chemistry Reserch.48 (4): 935. Lewndowski A Estimtion of hse Digrm for Room Temperture Ionic Liquids. Journl of Moleculr Liquids. 15: Mron S.H. nd Lndo JK.B Fundmentls of hysicl Chemistry. p. 10, Mcmilln ulishing Co., Ine., New York, U.K. Nogueir R. nd ires do Rego E.C Development Studies of Cptopril Certified Reference Mteril. Brzilin Journl of hrmceuticl Sciences. 47(). Sukrdjo Chemicl hysics. molds to 3, Rinek T Cipt, Jkrt, Indonesi. Tyoso B.W Upgrding Mterils Dt rocessing In non Sttistics. pp. 113, T upuk Sri Wijy, lemng. 3035

6 VOL. 13, NO. 9, MAY 018 ISSN ARN Journl of Engineering nd Applied Sciences Asin Reserch ulishing Network (ARN). All rights reserved. SULEMENTARY DATA The vlue of NCl concentrtion in the oiling solution is used to clculte the price using eqution (7). The experiment ws repeted for vrious concentrtions to determine the vrious vlue of. Hence, different vlue used to mke empiricl equtions in eqution (8) to (13) using lest squred method while m is the mollity of slt in solution. Exmple the clcultion of prmeter, for NCl solution with mollity ± 0.5 mol/kg. From the experiment the mollity of NCl solution found ws 0.64 mol/kg nd vlue oiling point rise (Δ T ) y mesuring the oiling temperture of NCl solution is 1 O C NCl N + + Cl For slt of NCL vlue of Vlence of N is Z + = = 1 nd vlence of Cl is Z_ = 1 For solven is wter, vlue K of wter = 0.5 Therefore the vlue of cn e clculted with eqution (7) follow: To look for constnts nd in the eqution (8): Σ = n. +. Σm m. K.(1 ( Z. Z ) T (1 (1. 1) Σ (m.) =. Σm +. Σ (m ) This eqution cn e converted into Σ = n. +.Σ m 9,47 = nd Σ m. =.Σ m +.Σ m 9, 5 =.9, , 3666 By sustitution otining = 5,643 nd = 1, 7 So eqution (8) ecomes = 5,643 1, 7.m otined 14.5%. Similr clcultion method is lso performed for nother eqution of which shown from eqution (8) to (13). The clcultion for other slt nd other mollity slt solution of CCl, AlCl 3, N CO 3, FeSO 4, Al 3 (SO 4 ), N 3 O 4, nd C 3 (O 4 ). Cn e conducted y similr method where the results re expressed in Tle

Which of the following describes the net ionic reaction for the hydrolysis. Which of the following salts will produce a solution with the highest ph?

Which of the following describes the net ionic reaction for the hydrolysis. Which of the following salts will produce a solution with the highest ph? 95. Which of the following descries the net ionic rection for the hydrolysis of NH4Cl( s)? A. NH4 ( q) Cl & ( q) NH4Cl( s) B. NH Cl & 4 ( s) NH4 ( q) Cl ( q) C. Cl ( q) H O & 2 ( l) HCl( q) OH ( q) D.