Reinald Panganiban John Salvador Ricacho Ryan Lee Ronquillo Experiment Experiment 9 ACYL C!P"#$S% C!P"#$S% SAPS A#$ $E&ER'E#&S $E&ER'E#&S I. INTRODUCTION Soap( and detergent( are (ub(tance( )hen di((olve in )ater can remove dirt *rom (ur*ace( li+e human hum an (+in (+in,, tex textile( tile( and othe otherr (oli (olid(d(- ./0r ./0ritan itannica nica-com -com,/ ,/ n-d n-d-1-1- &he &hey y are (ur*a (ur*acta ctant( nt( )hic )hich h mean( they help reduce the (ur*ace ten(ion o* )ater- &heir cleaning action re(ult( *rom their ability to emul(i*y the )ater (oluble2material( and +eep them a( (u(pen(ion in )ater- .3at4, 56661 7hat happen( i(, the )ater in(oluble material i( (urrounded and di((olved by the non2polar 8hydrocarbon group molecule( o* the (oap or detergent )hich are al(o +no)n micelle and the ionic ion ic 8ca 8carbo rboxyl xylic ic (a (alt lt di di((o ((olve lve( ( in )a )ater ter-- Em Emul( ul(i*i i*icat cation ion ha happ ppen en(, (, )h )here erein in the ma mate teria rial( l( di(per(ed in the )ater and then can be rin(e a)ay- .3at4, 56661
Figure 1. A Structure of soap (left) and detergent(right) molecules (Katz, 2000) &hey di**er on their )ater (oluble portion- Soap(, )hen in )ater, react( )ith metal ion( to *orm precipita prec ipitate( te( +no)n a( (cum )hile detergent detergent doe( not- .3at4, 56661- &hi( ma+e( the hard detergent (uitable *or clothe( )ithout di(coloration )hile the (o*t (oap *or the (+in )ithout irritation- Soap( are made *rom natural *at( and oil( )hile detergent( are (ynthetic(- ./$i**erence bet)e be t)een en So Soap ap an and d $e $eter terge gent( nt(,/ ,/ n-d n-d-1 -1 &he (oap i( (y (ynth nthe(i e(i4ed 4ed in a pro proce ce(( (( +no +no)n )n a( (aponi*ication by hydroly(i( o* *at( or oil( )hich )ill pre(ented on the experiment- .3at4, 56661
Figure 1. The Saponication Process
:n (aponi*ication, three molecule( o* (oap are created )ith a glycerol by product hydroly4ed *rom the e(ter group o* *atty acid(- E(ter( are one among the derivative( o* the carboxylic acid&hey are derivative( becau(e the hydroxyl group bonded to the acyl group o* a carboxylic acid i( replaced )ith other (ub(tituent(- &hey undergo the Acyl Sub(titution reaction but di**er in their reactivity or inter2conver(ion )ith each other )ith hydroly(i( reaction o* )ater a( evidence.Carboxyl$erivativeReactivity,/n-d-1
Figure 2.i!erent "ar#o$%lic acid deri&ati&es and their reacti&it% order. 'etrie&e from httpmhhe.comph%sscichemistr%care%studentolcch20car#o$%lic.html
&he ob;ective( o* thi( experiment are to ob(erve the general propertie( o* carboxylic acid(< to compare the acidity o* carboxylic acid( and phenol(< to veri*y experimentally the inter2 conver(ion among acyl compound(< to become *amiliar )ith the phy(ical and chemical propertie( o* *at( and oil( and to under(tand the chemical ba(i( o* the(e propertie(< to learn ho) to prepare (oap and to compare the propertie( o* (oap and (ynthetic detergent(II. RESULTS AND DISCUSSION =or the (olubility te(t, the )ater (olubility o* the carboxylic acid (ample( and their relative aciditie( )ere determined- &he *amou( adage 8li+e di((olve( li+e centered the te(t- &hu(, the polar )ater (hould di((olve the polar (ample(- ther +ey *actor( may in*luence the re(ult( on (olubility and acidity o* the (ample>-1 7ater Solubility Table 1. Experimental
SAMPLE
Results for the solubility on the water and the relative acidities of the samples SOLUBILITY
pH
Acetic Acid Soluble Light Red . Acidic 1 0en4oic Acid Soluble 0lue .0a(ic1 Sodium 0en4oate :n(oluble Red .Acidic1 :n )ater (olubility te(t, acetic acid i( (oluble in )ater- :t i( (oluble becau(e it ha( only t)o carbon atom(- &he C? and @ bond( are polar- Acetic acid i( polar (o it di((olve( in polar
)ater- :t i( an acid becau(e it donate( @ in (olution- &hi( )a( then indicated and (upported )hen blue litmu( paper turned red:n ben4oic acid, the C@ group i( attached to the (table ben4ene ring- 0en4oic acid i( al(o polar thu( ma+ing it (oluble in )ater- &hi( i( becau(e it *orm( (trong intermolecular hydrogen bond( due to it( C? and @- :n (olvation, the @ in )ater i( attracted to in C? and @ i( attracted to in )aterSodium ben4oate i( a (alt o* ben4oic acid- :n the experiment, Sodium ben4oate te(ted to be in(oluble in )ater but it (hould be (oluble- &hi( i( probably becau(e (odium ben4oate ha( a lo) (olubility pro*ile- &he C? i( polar and @ in )ater molecule( are attracted to the in C?&hen hydrogen bond( are *ormed- #a i( al(o attracted to negatively charged @2 in )ater )hich ma+e( the (olution ba(ic a( indicated by blue litmu( paper5-1 Relative Aciditie( o* Carboxylic Acid( and Phenol SAMPLE
10% NaOH
NaHCO3
Phenol
Clear Solution . di((olve completely1
0en4oic Acid
Clear Solution . di((olve completely 1
Clear Solution )ith a layer . immi(cible liquid1 Clear Solution )ith )hite particle( . 0en4oic acid did not di((olve 1
:n the determination o* relative aciditie( o* ben4oic acid and phenol, they are added )ith #a@ and #a@CB- &he ben4oic acid ha( C? that )ithdra)( electron( *rom the oxygen o* the @ group- &hi( ma+e( ben4oic acid a (tronger acid than phenol becau(e the @ bond become( ea(ier to brea+ and @ donation i( very ea(y Another rea(on *or the increa(ed acidity o* the carboxylic acid (uch a( ben4oic acid i( the re(onance energy o* the carboxylate anion- &he carboxylate anion ha( greater re(onance energy than carboxylic acid becau(e the anion ha( t)o (table re(onance contributor( )hile the carboxylic acid ha( only one re(onance contributor- &here*ore, lo(( o* a proton *rom carboxylic acid i( accompanied by an increa(e in re(onance energy An aromatic alcohol (uch a( phenol i( a (trong acid but i( )ea+er than ben4oic acid- Electron )ithdra)al in phenol i( not a( great a( in ben4oic acid- Another, there i( electron delocali4ation in phenol anion but not a( great a( in a carboxylate anion, )here the negative charge i( (hared equally by t)o oxygen- A( a re(ult, the re(onance energy o* the phenolate anion i( le(( than that o* carboxylate anion- Since ben4oic acid i( a (tronger acid than phenol, it( @ i( readily donated )hen reacted )ith #a@ ba(e- Phenol al(o lo(e( it( @ but not a( ea(y a( ben4oic ben4oic acid- 0oth al(o lo(e( @ )hen reacted )ith #a@C B-
Al(o, ben4oic acid i( more acidic than phenol becau(e the @2 i( attached to a carbon )ith another attached to it, leading to greater (tability )hen @ i( relea(ed-
0- @ydroly(i( @ydroly(i( i( the reaction o* a compound )ith )ater- @ydroly(i( o* acyl compound( )ill give carboxylic acid-
Table 2.*$perimental results of the samples+ reacti&it% #efore and after heating. Samples Acetyl Chloride
Acetic Anhydride Sodium 0en4oate 0en4amide
React!"s Be!&e Heat"' Ate& Heat"' @eat =ormation )ith 0ubble =ormation (mo+e( @eat =ormation =oggy Solution =oggy Solution #o Reaction #o Reaction Clear Solution Clear Solution #o Reaction #o Reaction $i((olved Clear Solution #o Reaction #o Reaction "ndi((olved Slightly $i((olved
Ac#t$ Acidic
Acidic 0a(ic 0a(ic
:n the experiment, the acetyl chloride )a( the only (ample ob(ervable o* a vi(ible reaction indicated by the *ormation o* bubble and heat- All (ample( (hould have been reacted to *orm their carboxylic acid( Acetyl chloride react( )ith )ater to *orm a carboxylic acid a( in thi( reaction%
&hi( reaction i( po((ible and occur( immediately becau(e the incoming nucleophile .@21 i( a (tronger ba(e than the leaving halide Cl2- &he product (olution i( acidic becau(e o* the (trong acid @CL Acetic anhydride react( )ith )ater to *orm carboxylic acid- &hi( i( becau(e the incoming nucleophile .2@1 i( a (trong ba(e than the departing carboxylate ion- And, ben4amide a( an amide dont react )ith )ater becau(e the incoming nucleophile i( a )ea+er ba(e than the leaving group o* amide- $ue to heating, ben4amide react( )ith )ater and i( ba(ic-
"/
NH3
C. Sap!"cat!" Saponi*ication i( a proce(( o* creating (oap(- :t involve( the u(e o* *at( and oil( that contain B e(ter group(- =or in(tance, coconut oil )a( u(ed in the experiment, )herein the B e(ter group( are bro+en do)n to B individual (oap molecule(-
C!c!"(t Ol
S!ap
D. C!mpa&s!" ! s!ap a"# #ete&'e"t &he (oap that )a( u(ed *or thi( part o* the experiment )a( produced via the (aponi*ication done by the experimenter-
Table 3. Ta#le comparing the soap and detergent hen su#-ected to di!erent tests SAMPLE
H$#&!l$ss )pH*
SAP
0a(ic
$E&ER'E#&
Acidic
React!" +t, ac# Cloudy )hite )ith no bubble( Clear (olution )ith bubble( on top
React!" +t, +ate& S!t
Ha&#
Cloudy
Cloudy
Clear
Clear
&he polar head o* a detergent i( negatively charged (o it i( an anion (ur*actant- 7hen detergent i( reacted )ith )ater, the re(ult i( a ba(ic a( indicated by blue litmu( paper- A( in the experiment, it )a( determined that only (oap ha( a ba(ic attitude )ith )ater and detergent te(ted acidic, thi( i( probably due to human error becau(e detergent( (hould be ba(ic in nature@o)ever, )hen it come( to the reactivity )ith an acid, there exi(t( an important di**erence bet)een the t)o that i( the (en(itivity o* (oap( to acidic condition(- &he experiment revealed
that (oap doe( not react and i( not (uitable in acidic condition( )hile detergent doe(- &hi( i( becau(e )hen a (oap i( in an acidic .p@D-F1, it protonate( the carboxylate group- &he protonated (oap molecule doe( not have a charged head, and (o it become( in(oluble in )ater&he (oap molecule( precipitate out thereby producing a cloudy mixture that lead( to the *ormation o* a (cum Another di**erence bet)een the t)o cleaning agent( i( their capacity to act in di**erent type( o* (olvent, (o*t )ater and hard )ater- $etergent( )ith ionic end and a nonpolar end are better reactant( to both (o*t and hard )ater mixture( due to it( *e)er tendencie( to *orm in(oluble complexe( ma+ing the emul(i*ication proce(( more po)er*ul7ith a le((er propen(ity to *orm precipitate(, detergent( are *ound to be good emul(i*ying agent( in the (eparation o* in(oluble molecule( in the (y(tem- @ence, the removal o* (uch in(oluble molecule( i( ea(ier than that o* the (oap(- &he (oap( are indeed (moother in appearance but due to it( inclination to create precipitate(, it( main purpo(e a( cleaning agent i( put into te(t- &here*ore, (oap( tend to pre(ent more inappropriate activitie( )ith di**erent reagent(- 7ith thi(, it can be a((umed that detergent( are more applicable in mo(t (ituation( than (oap(Em(ls$"' &eact!" SAMPLE
-EROSENE
SAP
>(t layer% Small bubble( 5nd layer% 0ig bubble( .upper layer1
$E&ER'E#&
>(t layer% Small bubble( 5nd layer% 0ig bubble( .upper layer1
7A&ER 0LA#3
5 layer(
0ecau(e li+e di((olve( li+e, the nonpolar .hydrophobic1 end o* (oap moleculeGdetergent molecule can di((olve the dirt .+ero(ene1 and the polar .hydrophilic1 end i( attracted to )ater molecule(- &here*ore, the dirt *rom the (ur*ace being cleaned )ill be pulled a)ay and (u(pended in )ater- &hu(, (oapGdetergent act( a( an emul(i*ying agent, a (ub(tance u(ed to di(per(e one liquid .oil1 in *orm o* *inely (u(pended droplet( o* )aterIII. C!"cl(s!" a"# Rec!mme"#at!"s
Acyl compound( are compound( that contain( a carbonyl group )hich i( directly bonded to an electron2rich molecule- &he mo(t )idely di(tributed acyl compound( are the carboxylic acid(Carboxylic acid( are the mo(t important o* the acidic organic compound(- &hey can be characteri4ed by their propertie(- Example, in thi( experiment their extent o* (olubility )a( te(ted and it )a( *ound out that due to the polarity o* their C? and @ bond(, they tend to be (oluble in )ater- &heir relative aciditie( )ere al(o te(ted- Carboxylic acid( are relatively (trong acid( a( bac+ed up by the (tability o* their con;ugate ba(e( .(alt(1- Acyl compound( can al(o be hydroly4ed to *rom their re(pective carboxylic acid( -La(tly propertie( o* (oap and detergent are *ound out to di**er- Soap( *orm (cum( in )ater )hile detergent( do not, becau(e detergent( contain (ul*onate group(- 0a(ed on the experiment, (ynthetic detergent( are better cleaner( *or clothe( )hile (oap, )hich i( made *rom *at( and natural oil(, i( better *or the (+in-
:n thi( experiment, there (eem( to be re(ult( that do not coincide )ith the theoretical *rame)or+Erroneou( methodology greatly a**ect( the re(ult, and the experiment i( very qualitative, (o per(onal error i( a big *actor- Care*ul handling o* chemical( and reading the manual )ill greatly help *uture re(earcher( that )ill u(e thi( a( a re*erence-
I. Ree&e"ces
"ar#o$%l eri&ati&e 'eacti&it%. (n.d.). 'etrie&ed from https2.chemistr%.msu.edufacult%reuschirtT$t1mlcr#acid2.htm i!erence eteen Soap and etergents. (n.d.). 'etrie&ed from http.di!erence#eteen.comdi!erence3#eteen3soap3and3&s3detergents Katz, . (2000). The Science of Soap and Detergents . 'etrie&ed April 24, 2056, from http.ch%mist.comSoap720and720detergent.pdf soap and detergent 8 chemical compound 8 ritannica.com. (n.d.). 'etrie&ed from http.#ritannica.comsciencesoap
. A"s+e&s t! /(est!"s >
Explain the di**erence in the (olubility o* ben4oic acid and (odium ben4oate in )ater7hich o* the t)o )ould you predict to be more (oluble in C@ClBH Explain &he ben4oic acid i( more polar than (odium ben4oate due to it( C? and @ bond(- So, ben4oic acid i( more (oluble in )ater- C@Cl B i( le(( polar compared to )ater and (o (odium ben4oate )ill be more (oluble-
5
0a(ed on the re(ult( in Part A-5, )hat can be (aid about the relative aciditie( o* phenol( and carboxylic acid(H Arrange the *ollo)ing compound type( in order o* increa(ing acidity% carboxylic acid, alcohol, phenol and )aterCarboxylic acid I phenol I alcohol I )ater Even though both contain @ group, carboxylic acid( are much more acidic than alcohol( due to the relative (tabilitie( o* their con;ugate ba(e(- :n an al+oxide ion, the negative charge i( locali4ed on one oxygen atom- :n carboxylate ion, ho)ever, the negative charge i( delocali4ed over both oxygen atom(- :n other )ord(, a carboxylate ion i( a (tabili4ed re(onance hybrid o* t)o equivalent (tructure(- Another, carboxylate ion i( more (table due to the re(onance (tability than phenolate anion- &hu(, donating @ i( more *avourable- La(tly, Phenol( are more acidic than alcohol( becau(e the phenoxide anion i( re(onance2(tabili4ed by the aromatic ring
B
0a(ed on the re(ult( in Part 0, arrange the *ollo)ing compound type( in the order o* decrea(ing hydroly(i( rate% acid halide(, acid anhydride(, e(ter(, and amide(- 'ive the theoretical explanation( *or he ob(erved di**erence( in reaction rate(-
Polar acid halide( are the mo(t reactive o* the carboxylic acid derivative( becau(e the electronegative halide atom (trongly polari4e( the carbonyl group- Acid anhydride( react in almo(t the (ame manner a( acid halide(, although at a (lo)er rate- nly 8hal* o* the anhydride molecule i( u(ed- &he other hal* act( a( the leaving group during the nucleophilic acyl (ub(titution (tep and produce( carboxylate anion a( a by2product&hu(, anhydride( are ine**icient to u(e, and acid chloride( are normally pre*erred *or introducing acyl (ub(tituent( other than acetyl group(- E(ter( (ho) the (ame +ind( o* chemi(try a( the *ir(t t)o compound( mentioned, but are le(( reactive to)ard nucleophile( than acid chloride( or anhydride(- &he (lo)e(t to hydroly4e are the amide( (ince their lin+age i( very (table
:( the (oap )ater mixture a true (olutionH Cite example( to (upport your an()er-
A (oap (olution i( not a real (olution but a colloidal mixture that arou(ed a*ter the addition o* (oap to )ater- :t i( con(idered a colloid, a cloudy mixture )here one (ub(tance i( di(per(ed evenly throughout another- 0ecau(e o* thi( e**ective di(per(al, (ome colloid( have are mi(ta+en to be (olution( (ince they have (imilar appearance(You canKt di**erentiate bet)een the (olute and (olvent molecule( even at the micro(copic level- :t i( completely homogeneou( *or a true (olution- &he particle( are invi(ible even under po)er*ul micro(cope(- =or example, mil+ (eem( to be completely homogeneou( but it i(nKt- !il+ i( actually ha( a (u(pen(ion o* *at molecule( )hich are not di((olved at allF
7hat i( a colloidal mixtureH @o) doe( a colloidal mixture ari(e )hen (oap i( mixed )ith )aterH
A colloid or colloidal di(per(ion i( a (ub(tance )ith component( o* one or t)o pha(e(- :t i( a heterogeneou( mixture )here very (mall particle( o* one (ub(tance are di(tributed evenly throughout another (ub(tance- !olecule( o* mo(t (oap are long chain hydrocarbon molecule( )ith an ionic group at one end- &he long hydrocarbon chain( do not interact )ell )ith )ater molecule(, &he e**ect o* the(e molecule( on the )ater (ur*ace i( to con(iderably )ea+en the *orce( bet)een )ater molecule( there, thu( lo)ering the (ur*ace ten(ion- 7ith thi( e**ect, it ma+e( the particle( to be di(per(ed- A( a beam o* light i( pa((ed through mixture o* (oap, (ome o* the light i( (cattered by the di(per(ed particle(, ma+ing the beam vi(ible *rom the (ide, thu( the de*inition o* the colloid( above i( (een .&yndall e**ect1-
n the ba(i( o* the litmu( te(t, are the (oap2)ater and detergent2)ater mixture( acidic, ba(ic or neutralH Explain the di**erence, i* any in the reaction( o* the (oap2)ater and detergent2)ater mixture( to litmu( papern the ba(i( o* the litmu( te(t, both mixture( are ba(ic- &here i( no great di**erence in the t)o a( it )a( a((umed that both mixture( are good electron donor( (ince in their (tructure( they both become anion(- Soap( undergo a hydroly(i( reaction upon hydration and a( a re(ult, they tend to be al+aline- $etergent2)ater mixture( are al(o al+aline but in a le((er degree-
M
7hich )ould you predict to have a greater emul(i*ying po)er in 8hard )ater, (oap( or (ynthetic detergentH ExplainSynthetic detergent( have greater emul(i*ying in 8hard )ater becau(e o* the pre(ence o* the (ul*onate group in detergent(- &he (ul*onate group doe(nt react )ith the calcium and magne(ium ion( in hard )ater to *orm (cum(, li+e (oap( do-
N
Explain the cleaning property o* (oap( and detergent( ba(ed on your ob(ervation( o* their emul(i*ying action&he cleaning action o* both (oap( and detergent( re(ult( *rom their ability to emul(i*y or di(per(e )ater2in(oluble material( .dirt, oil, grea(e, etc-1 and hold them in (u(pen(ion in )ater- &hi( property come( *rom their molecular (tructure(-&he (oap or detergent molecule( (urround the oil droplet( )hen a (oap or detergent i( added to )ater that contain( oil or other )ater2in(oluble material(- &he oil or grea(e i( 8di((olved in the al+yl group( o* the (oap molecule( )hile the ionic end allo)( the micelle to di((olve in )ater&he oil droplet( are then di(per(ed throughout the )ater, a( emul(i*ication ta+e( place, and can be rin(ed a)ay-
