Standardisation of HCL PDF

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Ai m: T od e t e r mi n et h ec o n c e n t r a t i o no f ah y d r o c h l o r i ca c i ds o l u t i o nt h r o u g ht i t r a t i o n . I n t r o d u c t i o n : T i t r a t i o ni sais a common laboratory method of quantitative chemical analysis to determine the concentration of an identified analyte. A titrant is prepared as a standard solution of known concentration and volume. The titrant reacts with a solution of analyte.to determine the analyte's concentration. The volume of titrant that reacted with the analyte is termed the titration volume. (Wikipedia contributors, 2019) Titration process involve neutralisation. Neutralisation is the reaction between an acid and a base to produce salt and water. In the neutralisation process, the acidity of an acid is neutralised by an alkali. At the same time, the alkalinity of the alkali is neutralised by the acid. (T a n , Y . T . &L o h , W. L . &T a n , O. T . , 2 0 1 6 )

a nb ed e fi n e da st h ea mo u n t o f s o l u t ed i s s o l v e di nas o l v e n t . T h e r ea r emu l t i p l eu n i t so f Co n c e n t r a t i o nc c o n c e n t r a t i o n . Th emo s t c o mmo nu n i t si n c l u d emo l a r i t y , mo l a l i t y , n o r ma l i t y , ma s sp e r c e n t , v o l u me p e r c e n t , a n dmo l ef r a c t i o n . T h ef o r mu l ao f c a l c u l a t i n gc o n c e n t r a t i o ni nt h es t a t eo f mo l a r i t yi s He l me n s t i n e , A. M. , 2 0 1 8 ) M=mo l e s/ l i t e r . (

Ap p a r a t u s : Pi p e t t e , p i p e t t efi l l e r , b u r e t t e , b e a k e r , c o n i c a l fl a s k , g l a s sf u n n e l , v o l u me t r i cfl a s k , r e t o r t s t a n d , wh i t et i l e , e l e c t r o n i cb a l a n c e , s p a t u l a , d r o p p e r , s t i r r i n gr o d Ma t e r i a l s : Me t h y l o r a n g e , s o d i u mc a r b o n a t e , h y d r o c h l o r i ca c i d , d e i o n i s e dwa t e r Pr o c e d u r e : Pa r t A: Ma k i n gaSt a n d a r dSo l u t i o n 1 .Ab o u t 1 . 3 go f t h ea n h y d r o u ss o l i ds o d i u mc a r b o n a t ei sa c c u r a t e l ywe i g h e dwi t ha1 0 0 mL b e a k e r u s i n ga ne l e c t r o n i cb a l a n c e . T h ema s si sa c c u r a t e l yr e c o r d e d . 2 .Ag l a s sf u n n e l i su s e dt oc a r e f u l l yt r a n s f e r t h es o d i u mc a r b o n a t e , al i t t l ea t at i me , i n t oa2 5 0 mL v o l u me t r i cfl a s k . 3 .Awa s hb o t t l eo f d e i o n i s e dwa t e r i su s e dt oe n s u r ec o mp l e t et r a n s f e r o f t h es o d i u mc a r b o n a t e . Wa t e r i sa d d e di n t ot h efl a s ku n t i l i t i sh a l f f u l l . Co n t e n t so f t h efl a s ka r es t o p p e r e da n ds wi r l e d t od i s s o l v et h es o d i u mc a r b o n a t e . 4 .Mo r ewa t e r i sc a r e f u l l ya d d e du n t i l t h eb o t t o mo f t h eme n i s c u so f t h es o l u t i o ni se x a c t l yl e v e l wi t ht h ec a l i b r a t i o nl i n eo nt h en e c ko f t h eb o t t l e . Th efl a s ki ss t o p p e r e da n dwe l l mi x e d . Pa r t B: St a n d a r d i s i n gaHCLSo l u t i o n 1 .A2 5 . 0 0mLp i p e t t ei sr i n s e dwi t ht h es t a n d a r ds o d i u mc a r b o n a t es o l u t i o n . 2 5 . 0 0 mLs a mp l e so f t h es o l u t i o na r et r a n s f e r r e di n t oe a c ho f t h r e e1 0 0 mLc o n i c a l fl a s k s . 2o r 3d r o p so f me t h y l o r a n g ei n d i c a t o r a r ea d d e dt oe a c hfl a s k . 2 .Ab u r e t t ei sr i n s e da n dfi l l e dwi t ht h eh y d r o c h l o r i ca c i ds o l u t i o nt ob es t a n d a r d i s e d . 3 .T h ei n i t i a l b u r e t t er e a d i n gi sr e c o r d e di nt h et a b l e . 4 .T h es o d i u mc a r b o n a t es o l u t i o ni st i t r a t e dwi t ht h ea c i du n t i l t h ei n d i c a t o rs h o wst h efi r s t p e r ma n e n t c h a n g ef r o my e l l o wt oo r a n g e p i n k . T h efi n a l b u r e t t er e a d i n ga n dt h ev o l u meo f t h e t i t r ei sr e c o r d e di nt h et a b l e .

5 .T h et i t r a t i o ni sr e p e a t e du n t i l t h r e ec o n c o r d a n t t i t r e sa r eo b t a i n e d . Al l t h et i t r a t i o nr u n sa r e r e c o r d e d . 6 .T h ea v e r a g eo f t h ec o n c o r d a n t t i t r e sa r ec a l c u l a t e d . Re s u l t s : T a b l e1 : T i t r ev a l u ef o r e a c ht i t r a t i o n Ti t r a t i o n 1 2 3

I n i t i a l Bu r e t t er e a d i n g( ml ) 0 . 0 0 0 . 0 0 0 . 0 0

Fi n a l Bu r e t t er e a d i n g( ml ) 3 0 . 6 0 3 0 . 7 0 3 0 . 6 0

Ma s so f Na O3=1 . 3 0 8 g 2C

Da t aAn a l y s i s : 1 . Av e r a g eo f c o n c o r d a n t v a l u e s : 3 0 . 6 0+3 0 . 7 0+3 0 . 6 0/ 3=3 0 . 6 3 mL =0 . 0 3 0 6 3 mL

2 . No . o f mo l e so f Na CO3 2 1 . 3 0 8/ ( 2 ( 2 3 . 0 ) +1 2 . 0+3 ( 1 6 . 0 0 ) ) =0 . 0 1 2 3 mo l

3 . Co n c e n t r a t i o no f Na CO3 2 2 5 0 mL=0 . 2 5 0 L 0 . 0 1 2 3/ ( 0 . 2 5 0 )=0 . 0 4 9 2 M

4 . T h e o r e t i c a l c o n c e n t r a t i o no f HCl E q u a t i o no f t h et i t r a t i o n : Na2CO3+2 HCl

2 Na Cl +H2O+CO2

O HCl 1Na 2C 3:2 0 . 0 4 9 2 MNa CO3: 0 . 0 9 8 4 MHCl 2

5 . Ac t u a l c o n c e n t r a t i o no f HCl E q u a t i o no f t h et i t r a t i o n : Na2CO3+2 HCl 1Na O HCl 2C 3:2 MaVa

2

2 Na Cl +H2O+CO2

T i t r ev a l u e( ml ) 3 0 . 6 0 3 0 . 7 0 3 0 . 6 0

MbVb

1

Max3 0 . 6 3=2( 0 . 0 4 9 2 ) ( 2 5 . 0 0 ) Ma=0 . 0 8 0 3 M Di s c u s s i o n : 1 .At t h ee n do f t h ee x p e r i me n t , t h ec o l o u r o f t h es o l u t i o nt u r n sf r o my e l l o wt oo r a n g e p i n k . T h i s i n d i c a t e st h a t t h ee n dp o i n t o f t h et i t r a t i o nh a sr e a c h e d . At t h eb e g i n n i n go f t h ee x p e r i me n t , t h e s o l u t i o nwa sy e l l o wb e c a u s et h ep Hv a l u eo f s o d i u mc a r b o n a t es o l u t i o ni sl e s st h a n7 . At t h e e n dp o i n t , t h es o l u t i o n st u r n sf r o my e l l o wt oo r a n g eb e c a u s et h es o l u t i o ni sn e u t r a l i z e dwh i c h me a n st h ep Hv a l u eo f t h es o l u t i o ni s7 .

2 .T h et h e o r e t i c a l c o n c e n t r a t i o ni sh i g h e r t h a nt h eo b t a i n e dc o n c e n t r a t i o n . T h i sc a nb ec a u s e db y p o s s i b l ee r r o r so c c u r r e dd u r i n gt h ee x p e r i me n t . F o r e x a mp l e , p a r a l l a xe r r o r wh i l et a k i n g r e a d i n g s . Be s i d e st h a t , t h i sc a na l s ob ec a u s e db yt e mp e r a t u r eo f t h es u r r o u n d i n g s . T h e e v a p o r a t i o no f t h es o l u t i o nma ya ff e c t t h er e s u l t so b t a i n e d .

3 .Asi mp r o v e me n t t ot h i se x p e r i me n t , a i r b u b b l e si nt h eb u r e t t es h o u l db ef u l l yr e mo v e d . T h i si st o e n s u r eamo r ea c c u r a t er e s u l t s . ( Ku l c z a k , 2 0 1 9 ) Be s i d e s , t h ec o n i c a l fl a s ks h o u l db es wi r l e d c o n t i n u o u s l yt oe n s u r et h ea c i ds p r e a d si nt h ea l k a l i s o l u t i o n . Sa f e t yp r e c a u t i o n s : 1 . Gl o v es h o u l db ewo r et h r o u g h o u t t h ee x p e r i me n t . Th i si sb e c a u s eHCl i sc o r r o s i v ea n dc o u l d c a u s ec h e mi c a l b u r n so nb a r eh a n d s . 2 . Sa f e t yg o g g l e ss h o u l db ewo r et h r o u g h o u t t h ee x p e r i me n t . T h i si st op r e v e n t t h ec o r r o s i v e c h e mi c a l f r o mc o n t a c t i n gt ot h ee y e sa n dc a u s eh a r ms / 3 . L a bc o a t a n dc o v e r e ds h o e ss h o u l db ewo r et h r o u g h o u t t h ee x p e r i me n t t op r e v e n t c h e mi c a l f r o m s p l a s h i n gt ot h eb o d y .

Gr e e nCh e mi s t r yCo n s i d e r a t i o n s : T h eGr e e nCh e mi s t r yp r i n c i p l e‘ wa s t ep r e v e n t i o n ’ i su s e d . F o rt h i se x p e r i me n t , e x a c t n e e d e d a mo u n t o f c h e mi c a l si su s e d . T h ec h e mi c a l so n l ywi l l b et a k e na g a i nwh e ni t i sn o t e n o u g h . T h i si s t op r e v e n t wa s t a g eo f c h e mi c a l s . T h eGr e e nCh e mi s t r yp r i n c i p l e‘ r e a l t i mep o l l u t i o np r e v e n t i o n ’ i su s e d . T h ec h e mi c a l su s e da r e d i s c a r d e di nap r o p e r wa y . T h ec h e mi c a l sa r en e u t r a l i z e db e f o r ed i s p o s i n g . T h i si st op r e v e n t t h e c h e mi c a l sf r o mp o l l u t i n gt h er i v e r .

Co n c l u s i o n : Ba s e do nt h er e s u l t o b t a i n e d , t h ec o n c e n t r a t i o no f HCl wa sd e t e r mi n e dt ob e0 . 0 8 0 3 M.

Re f e r e n c e s : K u l c z a k , V . ( 2 0 1 9 ) . T o pT i p sf o r Mo r eAc c u r a t eT i t r a t i o n s . Re t r i e v e df r o m h t t p s : / / www. y s i . c o m/ y s i b l o g / wa t e r b l o g g e d b l o g / 2 0 1 9 / 0 6 / t o p t i p s f o r mo r e a c c u r a t e t i t r a t i o n s T a n , Y . T . &L o h , W. L . &T a n , O. T . ( 2 0 1 6 ) . Ne u t r a l i s a t i o n . SUCCESSCh e mi s t r ySPM. ( p p . 2 0 3 2 0 8 ) . Sh a hAl a m, Se l a n g o r : Ox f o r dF a j a r Sd n . Bh d . Wi k i p e d i ac o n t r i b u t o r s( 2 0 1 9 ) . T i t r a t i o n . Wi k i p e d i a , T h eF r e eEn c y c l o p e d i a . Re t r i e v e df r o m h t t p s : / / e n . wi k i p e d i a . o r g / wi k i / T i t r a t i o n He l me n s t i n e , A. M. ( 2 0 1 8 ) . Ca l c u l a t i n gt h eCo n c e n t r a t i o no f aCh e mi c a l So l u t i o n . Re t r i e v e df r o m h t t p s : / / www. t h o u g h t c o . c o m/ c a l c u l a t i n g c o n c e n t r a t i o n o f a c h e mi c a l s o l u t i o n 6 0 9 1 9 4...