ADMINISTRATION OF THE LABORATORY

Reagents a nd special items

Due to the nature of the work prescr ibed in th is manual it is no t possible LO Lite acomplete ca ta log of materia l needed d ur ing th e year. H owever, ex per ience has shown thatthe ma teri al listed below will su ffice to meet all bu t the un usual req uests o f the students.Add it ional needs can usually be met from the ord inary stocks ob ta inab le from the laboratory

. stoc k room or from local hard ware, f,'Toccry, and oth er stores.

(COO H)C H,C-(O H) (COO H)-CIl,(COO H)

Coba lt (II ) ch loride CoCI:: · 6H ::0Cobalt (II) nitra te CO(NO;lh ' 6H::0Copper Cu: shot, #8Copper Cu: strip, ca. I em by 5 cmCop per e u; wire, hare, # 18Coppe r (II) ch loride CuCI:: · 2H :: OCopper (II) n itra te Cu(X O:1h ' 3H::OCopper (II) ox ide Cc OCo pper (II ) su lfa te CuSO ~ ' 5H::0Egg albumin; driedFerr ic ammon ium citra te. com mon nam e for

im pure { XH~h ' ~ Fe[(COOh C3H ..O Hh ~Gela tineD-Gl ucose CGH12 0 flIodine I::Iron Fe; filingsIron Fe; wire , hare. #18Iron Fe; wire , ha re , #2,1Iro n (II) chl or ide FeCI:: ' 4H 2 0I ron (II I) chlo r ide FezCI,• • 12HzOIron (III) n itrate J.'e (NO:.b · 9H ::0Iro n (II I) oxide Fez0 3Iron (II ) su lfate FeSO~ ' 7H::OIron (II) sulfide FeSLead Pb: shot . # 8Lead Ph ; strip, ca. I em by 5 emLead (II) aceta te (CH ;\COO):: Pb · 3H 2 0Lead (I I) n itrate I' b (N O:\)::

S O LI n R EAGE:'\TS

Ca rbo n C; cha rcoal. powderedCa rbo n C; graphi te powde rCarbo n d iox id e CO2 ; solid ; Dry IceCation exc hange re sin; Dowcx 50, hydrogen

for mCation exchange resin ; J'er rnutit QCharcoal: act iva ted (Darco brand)Chromium (I I I) ch loride c-ci, · 6H20Ch romi um (I II ) oxide Cr::O:\Citric acid

Agar agarAl um ina ; act ivated AL,l0 :\ ' xH::OAluminum ,\ 1; fo ilAl uminum AI; gran ular , 8 meshAlumi num AI; tu rn ingsAluminum chloride; anhydrous AICI;"!Alumi num ch loride AICI:1 • GH :: OAl uminum sul fate .-\ ldSO~h · 18H::OAmmoni um acetate CH:ICOONH~

Ammoni um carbona te (N H ~ )2 CO;l

Ammonium ch lor ide XH~CI

Ammonium d ichromate (NH ~ hCr :: O j

Am monium d isulfa tohe xnaquoferra te (I I)(XI I ~ h [Fe(SO ~ h (0 H 2)fl]

Am mon ium nitrate NI I..XO:1Ammoni um sulfate (N H~hSO~

Anil ine hyd roch loride C'l H.; XH 2 • H CIAn iline yellow dyeAnt imo ny SbAn tim ony trich lor ide ShCI;\Ar senic (II I) ox ide As..O uAsbestos fiber , acicl washedAzoxyben-enc C,;H ;;(:\O:\)C,;H .;Bariu m hyd rox ide Ba (O Hh ' 8H 2 0Barium peroxide BaO::Hen- idc ne ( X I I :: C ,; H~h

Bismu th (II I) ch lor ide B i Cl ;~

Borax, n ude; if not ava ila ble, conta mi natesodium tet raborate with a li tt le sodi umcarhonate and calcium carbonate to sim­ulate crude mater ia l.

Boric acid II ::BO :\Cak ium Ca; lumps, pelle ts or tu rni ngsCaki um carbide CaC::; in sealed contai nerCalcium chloride Cael::; anhydrousCalcium h yd rox ide Ca (O HhCal cium pho sp hide Ca;~ P ::; in sealed conta inerCalcium su lfa te CaSO.. • y:! H ::OCa lcium sulfate CaSO.. • 2H::OCarbon C; cha rcoal, block

87

Lead (I V) ox ide PbO zLead monoxide PbOTrilead tetroxide Pb:\O~

Lith ium chlori de LiCI:\fagnesium :\Ig; gra nula r. 20 mesh:\lagn 5ium Mg; ribbo n:\l agn 5 ium carbona te :'o lgCO:!:\Ianganese (II) ch loride :\l nClz • -lH 20.:\ fanganese di oxide :\lnOzXlangan ese (II) sulfa te MnSO~ · H zOMarble ch ip s im pur e CaCO:!" fercury (11) chloride HgCl z:\Iercury (I I) ni trat e I lg(NO:I ) 2 • H 20Na ph tha lene Cl l1 l- l ~

fJ·N aph thol C1uH , O l-lN ickel (II) n itra te Ni(NO :1h ' 6H 2 0Ni ckel (II) oxide NiON icke l (II) sulfate NiSO~ · 6 1-1z0Z. -t-Dinitrophe nyl hyd razine

C, OZh Clll-1 ;\ N I I N l l zOxalic add (CO O Hh ' 2HzOPara ffin C. H . +zPhenol C" H ,..O HPhth a lic anhydride C,; J I~ (COhO

Potassiu m brom ide KRrPo tassium ca rbona te KzCD a • 1.5H zOPotassium chlora te KCIO :!Pot assium chlor ide KCIPot assium chromate KzCrO..Pot assium cyan ide KCXPotassium d ich ro mat e KZCr2D ,Tri potassium hexacyanofer rare

K:I[Fe(CN),,1'Tet rapota ssilim hcxacynno rriaq uoferra te

K..[Fe (C N),,(1120):IJPota ssium hyd roxide KO I-I ; pe lle tsPot assium iodate KIO ;\Po tassium iodide KIPotassiu m n it ra te KXO :\Po tassium permallgana te KMnO..Potassium su lfa te K z SO ~

Potassium th iocyana te KSC NResorcinol C" H j (O Jl hRock salt im p ure NaCISal icylic add HO C,;l l j CO OHS;lI1d impure SiO zSilver nitra te Ag:'\ O ;1Soa p. mi xture of sodi um salts of fatty ac ids,

im pure; flakes or gran ules

88

(contin ued )

Soda lime; m ixt ure of 1'\aO Il and Ca (O HhSodium ace ta te C H aCO O Na ' 31-12°Sod ium perbora te. ~aBOa ' 41-1 z0Sodium tet rabo ra te ~azn~O.· IOH zOSod ium bro mide NaRrSodi um ca rbonate Na: CO:1; anhydrousSod iu m carbo na te .....a: CO :\ • IOH zOSodi um chloride Na CISod ium d ichroma te Na2Cr20 , . 2112°Sodium h ydrogen su lfa te 1'\aIlSO .. • H 20Sodi um hydroxid e NaO H ; pe lle tsSodi um iod ide Na ISod ium nit ra te Na XO :1Sod ium ni tr ite Nai\'O~

Sod ium ox ala te (COO)~ ~a ~

Sucrose, impure ; dar k bro wn cane sugarTrisod ium phospha te

i\'a ;:PD j ' 1 2H~O

Sodium di hyd rogen phospha te1\"aH:POj ' H~O

Sod ium monohydrog en phospha teXa~ HPO~ ' 7 H~0

Sodium po tassium tartrate~aOOC(CHOHhCOOK ' 4HzO

Sodi um pyrosul tire XazS~O:.

Sod ium sul fate 1\""250 ..Sod ium su lfite Na 2SO:\

Sod ium thiosu lfa te N'a2S20:\ ' 5H20Starch . pota toSteel wool; # O()

Sucrose C 1 : 1122 011 : ca ne suga rSudan red dyeSu lfunil blue d yeSu lfur S

T in Sn: gra nu lar, 30 meshTin Sn: Illo s~y

Ti n ( II) ch loride SnCI 2 • ZJl:OT itan ium d ioxide T i02

Urea CO C:, H: )2wood sp lin tsZinc In: gran ula r. 30 me shZin c I n; mo~sy

Zinc Zn; str ip. ca . I em by 5 ernl in c carbo na te ZnCO aZinc ni trat e Zn(NO:1h · 611: 0Zinc oxide l nD

Zinc sul fa te ZnSO~ • 711:=0

Solutions and liqu ids

N ote : I n those cases where the concentrat ions of solu tions are not specified in th isman ual , solu tions of the concentrations listed here should be used. In those cases wheresolut ion concentrations are speci fied, but differ from those listed here, the student is ex­pec ted , as an exercise , to prepare his own solu tions eithe r by diluting a stoc k solu tio n orby dissolvin g a weighed quant ity of solute 1Il the proper amount of solvent.

T hese solut ion s shou ld be available, 1Il sets of bon lcs, conve niently set ou t 1Il thelabora tory:

Acetic acid C H ;\CO O H , 3-MAcet ic acid C H :\CO O H . glac ia lAmmonium hydroxide N H 40 H , 3·MAmmonium hydroxide

:\ H 4 0 H , cc nce nt ra redH ydroch lor ic acid H CI, 3·MH ydro chlo ric acid H C I, concent rated.\ (e thy l orange, 0.1% ; in d ro pping boule

Ninic acid H NO;\, 3·MXitric acid II NO :I , concentra tedPhcnolpluhale in C~O Il1404' 0.1% : in drop-

ping: bottle . Dissol ve I g in GOO m l of 95%etha nol an d add ·!OO m l of wat er

Sodi um hydroxide NaO H , 3-MSulfuric' acid H 2S0 4, l.5-MSulfuri c acid H~S04 ' concen trated

Carbon tetrachloride CC I4Chlo ro for m CI IC I:1Eth yl ether C~ H ...OC~H .-,

Formaldehyde . ca. 40'%aqueous

T hese liqu ids sho uld be placed III the hood :

,\ <etyl ch loride CH :\COCIBro mi ne Br2 : in d ropping bo tt leBro m ine wa ter; a sa t ura ted so lut ion of Br z in

wa ter with a litt le ex cess Br2 in the bottlelten zene CnH ()Be lllO}'1 ch lor ide C,JI ..,COCI

T hese liq u ids should be avai lable from the side shelf:

Ace taldehyde C H ;;C H OAcetone C II: ;COCH :\I/·,\ my l alcohol C..,1l 1 1 0 H.·\ lum in utll chloride A ICI:\, 3-.\1..Yluminum nitra te AI(:\ 0 ab . I-MAm mon ium chl o ride ;,\H 4CI. 1·.\1Ammonium oxala te (COOh(i\H4):!, 0.25-MAm mo nium sulfate (i'\H4bS04' 0.25·MAm mon ium su lfide (N H l):! S. 3·MAmmonium th iocyanate " H 4SCN, 0.5-MAniline C,;H ...NH~Barium chl o ride BaCl :!, O.25·MBism uth ( III) xnrare Bi ( :\O ;~ h , 0.2-MBrom cresol green (ind ica tor), 0.05% ; in d ro p-

ping: bo tt leII-Btlly l aIr olm l C4 H H O H/I . But yl bro m ide C411i. Brsec-Buty l bromide C4Hjl BrCadmium ch lor ide CdC I:! , 0.25-.\1Ca lcium ch lori de CaCI~ , 0.5·.\1Collod ion U .S.P. so lution in et herCopper (II ) ch lo ride CuCI:!. I-MCopper (II ) sulfa te Cu S0 4. 05 ·M

89

Ethyl a lcohol C:!H .-. O II , 95%I , 2·Did lloroe tha ne Cll ~C ICH :!CI

(;I yferi ne CH~OIICHOHCH~OH

H ydro ge n peroxide H~O~ , 10%Iron (II I) chlor ide FeCI;\, 0 .5·MKerosen e CHH n + ~ , impu reLead (II) ace tate (C H:;COO h Pb, 0.25-MLead (II) n it ra te Pb(l\'O:;b 0.25-Mxtagn csium ch lo ride ~ lgCI ~, O.25-M:\la gll esium ni tra te .\ lg( i'\O:J2' I-M.\fagn csiu m sulfa te .\ lg S0 4• I·M.\bnganese (II ) sulfate MnS0 4, 0.25-M.\lernlrY Hg: in bottle fitted with dropper.\ l('rcm )' (I I) ch lori de HgCI:!, 0.25·M.\ fernt ry ( II ) nitr a te H g{l\'O:lb I ·M,\le thyl alcohol CH:10 IlX id..e l (II) chloride i\iCI2, 0.25-M

Nit robe nzene CG I-I .-.l\'O~

O leic arid C~ H I,CII: CHC, H 14CO O HPar a ffin oilPhosphor ic acid H:I P0 4, (j-MPotassium bromide KBr, 1-,\1Potassium chro ma te K2 Cr04• 0.25-M

Potassium dichromate K~Cr~O" O.S-AtT r tpo tasstu r u hexacyanoferra teK~ [Fe(CN) ,;] , O.S-At

T etrapotassium hexacyanolerrateK4 [Fe(CN )l> J, 0.5-M

Potassium hydroxide KO H , 3·MPo tassium iodide KI , I-IIIPo tassium permangana te KMn04 , 0.01·A1Pot assium thiocyana te KSC"':, I-MIsopro p yl alcohol C;\H , O Ha- Propy l alcohol C;IH 'jOHSilver n itra te AgNO a, 0.5·11ISodi um chlor ide NaC!, I-IIISod ium fluo ride Na F, O.5·11ISodiu m hyd rog-en carbona te NaHCO;I' O.5-A!Sodi um n itra te NaN O ;\, I-M

Sod ium oxala te (CO ONab O.25-MSodiu m silicate Na:!O. xSiO~; _10° Bc.,

weigh t rat io N at O to SiO:!, ca. 1:3.25

Sodi um sulfate N"a tS0 4 , 0.5-11IStro nti um chlor ide SrCl~ , 0.25-MT hymol blue (indica to r), 0.05% : in d ropping

LottieTin (II) chloride SueL.! , 0.5·;\1Toluen e CHII ;, CII;jTurpent ineUn iver sal Indica tor .. tVinegar (a 1% ace tic acid solution lIlay be

subst it ut ed)

Zinc chl oride ZnCI :! , 3·MZinc su lfate ZnS04 , I-M

.. 0.050 g bromthymol blue0.013 g methyl red0.100 g phenolphtha lein0.005 K thymol blueDissolve in 100 ml of 95% ethanol. Add O.05·,\f Na O H umil green . Dilute to 200 nil with water.

t Foster, L. S., and Orunrtest, I. J.. J. Chern. Ed uc., H , 274 ( I!J37).

N ote : Due to hydrolysis, solut ions of some salts of the heavy metals will be cloud y.Addition of a few milli liters of the proper acid (hydrochloric acid for chloride salts, forexam ple) will repress the hydrolysis and d ear the solu tion.

Solutions of the lower valence states of some metals oxi di ze, on standing, to the highervalence state. T hese solut ions should be fre shly prepared (j ust before use) from sol ids ofkn own com position, or, if earl ier pre pa ration is necessar y, an exce ss of the metal itself putin the bottom of the bot tle and a li tt le excess of the correspondi ng acid added. (Such bottlesshould be stoppered wit h one-hole rubber stoppe rs fi tt ed with a Bu nsen valve in the hole.)

Ca tch-a ll List

The equi pment issued to each student at th e begin ning of the year suffices for mostof h is needs. For practic al reasons, however , not all needed equipment can be placed inhis han ds for the ent ire year. O ften, a special piece of eq uipment is used only for a shortt ime; or, differe nt students, from year to year, will request d ifferent items in the courseof wor k on the same problem ; or, the equipment may be too delica te to use witho ut dosesupervision, too bulky to store in a small space, too costly to purchase in large q uantities;and so on .

It is recommen ded that th ese items be ava ilable for use when needed :

Aitch-ru -ess cartridges (source of H 2 S, pro ­priet a ry-available fro m laboratory supplyhouse)

Am met er sAlli gator d ips (obtained from electro nics su p­

p ly hou se)

90

Asp irators (to fit water ta ps)Balances (various capacities and sensi tivities)Blanke t, fire smotheri ngBlast burnerm ow pip esBuch ner funne ls

CandlesCentr ifuge. and centr ifuge tubesC lo th swa tches (small , ca . 5 r ill square ; pref­

era hly wh it e. Ace tate r ayo n , cotton , dacron ,n ylon , silk, \1'001 , etc.)

Copper wire, insu la ted , # 18 sugges tedCork bo rers (asso rt ed sizes; and sharpener)Cotton , abso rb entDesicca torsDirect current source (p refera b ly var iab le. 0

10 10 or 15 vol ts, with attached voltmeterand a mme ter)

Electri c ho t p la tesEmery doth (as sorted gra des, coa r se to fine )Filter paper

(asso rt ed porosities and d iam eters)Fire ex tingu ishers, var io us typesFir st a id cab ine t, well -stoc kedHot air drying deviceG lass \1' 0 0 1

Cooch crucib les, with pla tesGraph ite rods (pencil "lead " o r anode Irom

dry cell)lee, cr ushedInca ndescen t lights, type 46 or 47, 6 to 8 volts

(and socket to fit)Iron dishe s (assorted sizes and sha pes)Labels, g umm ed paperMenur)' ba romet er (o r a nero id if a mercury

barometer is not ava ilable)Meter sticks::'\ails, 3d fm ish ingX ich rorne wire. # 18 sugges ted

O ffi ce sup p lies (erasers , gum me d ta pe. pa perdi ps, rubber bands. ruler, scissors, etc.)

Pe troleum jell y (Vaseline )pH meterpH test paperPi pets (asso rted, fro m sma ll sizes, fra ctional

milli liters, I ml to 50 Illl)P latin um wire, #24 suggestedPneuma tic troughsPotassi um iodide-starch test pa perl'ycnomctersPyrex or Kim ax tubing (assorted diameters, 3

m m to 15 mm)R efrigerator (used infreq ue n tly, need not be

immed iately accessible)R u b ber halloons (small sizes)Safety shower (p u ll lan yard to ac tua te]

Speci fic gra vity bottles

Stopcock grease

Stop wa tch

Stra ight p ins

StringTh read

"Tin" cans (assorted sizes a nd shapes)

Vacuum tube voltmeter

Vacuum p ump. mechan ical

Voltme ters

Volumetr ic flasks (var ious sizes)

\ Vo rksho p equipment and su p p lies (fro mhammer. n ai ls, saw, screw d ri ver-throughportab le d ri ll-to ba nd saw a nd la the, themore complete the be tter

Memora nda for the First Few Laboratory Period s

THt: FIRST i-zaron :

I. Assign in d ivid ua l locker or drawer space to the students.

2. Demonstrate the use of safety dev ices-fire ex tingu isher, fire blan ket . safety shower.etc.

3. Emphasize the im porta nce of first aid treat ment, even for m mor accidents.

4. Describe the procedure followed whe n corrosive l iq uids are spille d on the cloth ingor skin, in particular, the eyes.

5. Advise students how to obtain ex tra p ieces of eq uipment for tem pora ry use an dhow to effect replacement of broken items.

6. Provide a sheet of paper to be signed by each student in cert ification that all equip­men t listed on page x ii i has been received by hi m.

91

7. The instructor may prefer to provide some or all of the items listed on page XIV

whic h th is ma n ual requ ire s the stude nt to provide. T hi s is, of course, a matter to be decidedlocall y. Items not to be furn ished by the student himself should be provided by the in­structor; hence thi s reminder.

Tns SECO ND P ER IO D;

l. Check to see that items to be provided by the student an d brought to the laborator yhave been procured.

2. Give a short exam inat ion on the material in the sections "T o the Studen t" an d"Safety in the Lab oratory."

3. If desired, provide a few sam ple wash bo ttl es as models. It is helpful to exhi bi tone or two glarin g examples of poor work.

4. Exam ine the student's stirring rods, bent tubing, and wash bottl e. \Vhen properlyaccomplished , ini t ia l manual (in three places) .

5. Examin e student's en tr ies at the end of the sections on the burner and on glassworki ng.

L ATER LAB ORATORY PER IO DS:

Add itional remind ers to in it ial the manual and ex amine the student's work will notbe cited. T he suggestions whic h follow list only those po ints to be not ed wh ich are noteasily recogni zed in a cursory reading of the manual. Also, since some students begin to

sho w more ra pid progress than others at th is point, fu rt he r reference to items on a num beredday basis cannot be made. In the order in whic h they appear in the manual, then ;

l. Demonstrate how to read the barometer.

2. If nece ssary, demo nstrate collect ion of CO 2 by direct (downward) displacement ofthe an- in the collecting bottle.

3. If desire d , set up a sample filter in g exhibit. I t is helpful to use several pieces offilter paper, first fold , second fold, ctc ., in a series to show the successive steps of fold ing,tea ring the corner, fitting to the fun nel, etc.

4. Set the laboratory oven at ca. 1100 C for drying the barium chroma te.

5. See that burets are ava ilable, as the students req u ire them.

6. As the studen ts finish Part I collect their wr-it ten assignments on the five most IIIl­

portant safety ru les.

7. Di vide the students in to pairs, as they become ready, for the work in Part I I.

92