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Fonrrula of acid

6 (a) The pK" values o{ four carboxyiic acids are listed in the table below

KouhtI

rlr^- r''.r1l'\T #Qcf

i6m)

6(b)

ii) Describe afld sxptair'r th trrd in ecisic slrengtlt shown by acids L2 and:t>t \fiar\re *^t\ ){Ii}Giveanexplanationfolt|.led?fferenceinthepKav*luesforacids2and4{iii} Calculste lhe sf a 0.0't0 rnol dmi solu'tion o{ proparroic add (acid 1}

or| "-.EtPu(' -'{-'1 (rLrlThe sotubirity produnt,.Kr*, o{ magnesium hydroxide h*e a lrglnqds3lj{e-$g

iilwri .e an expre*ion for tne@, $taling its unitc

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If 0.40 nr':l oflr:Hi aadiJ 50 **;l of 0: ia r.i drli c+aiaiss il allc"l'edtoreact ratheprFlence,,icatal-+-.-.r pfotior*...ffioaiirnrr'lJ3trf alequiliL,riusri* extabli:lred' the feldof I'{O ii l'-ltc b-v l]lo}e' J*ii"ttt* tftu u"*tUtr-. 'rf ursl of }ffl ptodlrced.

Cnl'eo tLar tire teactiot '{ -?B iv:ecoud atdet'

Sl:etctr the grapL'; rrf (il couceqh atic'l] of A r'et:trs tiue :urd (ii) t:ate '"'ert?scccceltratioa of $-- I ;ru time is as g{v'etl l-relota-If rbegffiphot 1* to.

t2m)

(2m)7(e)

7 (f)8 {a)B tb)

tfAtL..J i rnoL'l dra-:'

10 i i nrn"'0(i*lcr{ateiil the ral* cctg-rlnlr{nl fire uritial colceobatios

of (3m)(2m)(2m)ISueqest rl:e urechn:ristu f'f,r'the reactrsfl il'-":t--'

'a hatflnccd c*luuriun ftrr thc prcpur'ation of{iiJ State the ref,gcn(s1 conditions nnd wriieamtn(rni a I ronr gqlgilumjglts-

lrirric scirl is ohtrrinerr lnrnr afimoflia by rhe ostwuld's process, Nitric acid undergo+rconrprere dissocjrtion i,, ;;;Jr;;-;;;r,*- rhc hvdmgen irn enrt the nilrxte i(ln'

ji;outii'IerhePrei}e'ationcfnitricacidfrqnramnroniaio'1;1qt}tlrv:ald'sFroce$s.(.;iJ Det*]:min$ rhe {)xidntion rtate of nitrogen in niuic acid"(iii)frrurv i1''s 1's" 'is diagrartt lirr the nitrate iolr and statn its thape' N$f

(13m)

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'10 (a)

1o(b)

10 (c)

A rSuthe{ir, po\rnet I[ is rlxfhesised Bocrl rnotronrrs fl'ald Q rhoum belor'riP: H0fl}I1CTI;,SH aud q : UOrC-S-COgt

{ i } }farne,*his aluthetic F*l}*tet Rasd d*a r q5--h5lryEgthi: polluer'( ii ) state tbe t1pe, ,rfpal}rr*risatisn ttr*t t+kes, place ss:iag the fsru:*tios of R ald glr'e

one n*e of R ib cr:r- dailYlife'Draw the structural formulae of the organic products obtained from the reactions ofaminoethanoic acid, H 2 NCH , COOH, with

{i} aqueous sodium hydroxide(ii) sulPhuric acid(iii) nitric (lll) acid(iv) ethanolState the acid-base nature of each of the organic

$vK,

{5rn}

(2m)Grystal of aminoethanoic acid/ glycine melt between230 and 235 u C' Explain why the

melting point of aminoethanoiJacidl glycine is higher than that of hydroxylethanoic acid'HocH 2 GOOH (m.P 75 - 80 o c)

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Theplssiblernolecr'tlalfornu|aeofthec|r|.oridesofanelementXareXC|,XCh.andXC|a.ciate ,r'r kJ molt1, fo' rn* *t"**nt X' chlorine' unJ'nu chlorides of the

element X are givern

Xis; --+ n1rtt enlhalpychange of alnmisatian ol X * +'14S

xis] '*-> x"qs) l;e-; ;;"ili:;:'t- enersv oi o ; +736X+iql -*:l 1r*igi'+ e-; secord icnlsallnn *-ot'gy of X = +14d8X""{ i--J,,-{.1.iu*,thirdionisati00energvni)li cl,(s:) -;t"*f ' ' -lll:]:v J'nsu oi;rornisalion ol ct =

+'121

c,.,,)- ._ ___,?li,lur, :*;Xl;l;ll . -l:i^ ' *3s4lattice energY of XCh ; -zbu1lalrrce energy of XCh = -5440

EnthalPYas follotrys:

By l"rl,rns the r:rithalpv f lliflb*l,iil,.,ll:.':-.::ililJi:['1"';:*i:'#3::iitl5,'iJi'il'ip+ (15m)

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