chemistry project class 12 on presence of acetic acid in samples of curd

7/22/2019 chemistry project class 12 on presence of acetic acid in samples of curd

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InvestigatoryProject onhemistry

For the session 2013 -2014

To detect the presence of

lactic acid in different samples

of curd

Submitted by :

Upasana Sahoo

Std - XII

Roll No.


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The investigatory project on chemistry for the year (2012-13) on

the topic

To detect of presence of lactic acid in different samples of curdSubmitted by

Upasana sahooStd-xii

D.A.V. public school

Sector -6,CDA, Cuttack

For the fulfillment of terms and condition set by the

Central Board of Secondary Education (CBSE) for ALL

India Senior School Certificate Examination

(AISSCE) 2013- 14

Project supervisor

Mr. Sambit Mishra

M.Sc, M.Phil (chem.), B.Ed

Dept of Chem.

DAV public school, Sec 6, CDA, Cuttack

PREFACE


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BONAFIDE CERTIFICATE

This is to certify that the project entitled TO DETECT THE

PRESCENCE OF LACTIC ACID IN DIFFERENT SAMPLES OF

CURD by UPASANA SAHOOis in accordance to the topic allotted to

him. This project is submitted for the fulfillment of terms and conditions

of CBSE for ALL INDIA senior secondary certificate examination

(AISSCE) 2013-14. It embodies the original work done by him under the

supervision and guidance of

Mr. Sambit Mishra

DEPARTMENT OF CHEMISTRY

D.A.V PUBLIC SCHOOL , C.D.A , CUTTACK

Signature of student signature of teacher


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ACKNOWELEDGEMENT

I express my deep sense of gratitude to my teacher Mr.

Sambit Mishra, Dept. of chemistry , DAV Public school , cuttack, for

his constant encouragement , valuable guidance and inspiration without

which the project could not have been successful.

I am grateful to my parents, who provided their valuable

suggestion for completion of this project and encouraging me throughout

the tenure of this project.

UPASANA SAHOO

D.A.V. PUBLIC SCHOOL

C.D.A , CUTTACK.


5/20

DECLARATION

I, Upasana Sahoo of Std-XII of DAV Public School,

CDA, Cuttack, do hereby declare that , this project entitled

TO DETECT THE PRESCENCE OF LACTIC ACID IN

DIFFERENT SAMPLES OF CURD

Submitted for the Chemistry Practical Paper for All India Senior School

Certificate Examination (AISSCE) , 2013-14 consists of original work

done by me under the supervision and guidance of my chemistry

teacher.

D.A.V. Public School Upasana Sahoo

Std- XII , Science

Date : Roll No. :


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AIM OF THE PROJECT

To detect the presence oflactic acid in different samples

of curd


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Reagents and apparatus

Reagents

1. Different samples of curd2. Sodium carbonate solution3. Ferric chloride solution4. Sodium hydroxide solution5. Phenol6. Test tube7. Test tube stand8. Glass rod9. Beaker10.Spatula


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PRINCIPLE INVOLVED

LACTIC ACID present in the curd is obtained by

fermentation of milk by bacteria LACTIC BACILI.

[()]

As LACTIC ACID contains-COOH group and alcoholic

group the tests which are characteristics of these

groups such as-

CARBONATE TEST shows the presence of COOHgroup.

FERRIC CHLORIDE TEST by formation of colouredcomplex.

Change of violet colour of phenol with ferricchloride to yellow on adding is due to thereplacement of phenol from ferric complex.

It gives IODOFORM TEST showing the presence ofsecondary alcoholic group which is bonded to

methyl group.


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PROCEDURE:-

The following tests are performed with COWS MILK CURD.

FERRIC

CHLORIDE

SOLUTION

OBSERVATION INTERFERENCE

2 drops of isadded to 2 test

tubes , ne with 2

ml of curd and

other with water.

The curd solu-tion turns yellow

while water

remains

colourless.

-OH group ispresent

CARBONATE TEST OBSERVATIO

N

INFERENCE

2ml of COsolution is added to 2ml of curd

Effervescence

volved due toformation of

CO

-COOH group is

present

IODOFORM TEST OBSERVATION INFERENCE

Strong iodinefollowed by

NaOH is added to

2 of curd

solution.

Yellowcrustalline pp. of

iodoform is

formed.

Secondaryalcoholic group

is present.


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PROCEDURE:-

The following tests are performed with GOATS MILK.

GOATS MILK CURD.

CARBONATE

TEST

OBSERVATION INFERENCE

2 ml of NaCO

is added to 2

ml of curd.

Effervsence is

observed due to

formation of CO.

-COOH group is

present.

FERRIC

CHLORIDE

SOLUTION


2 drops of ferric

chloride is added

to 2 test tubes , one

with 2 ml of curd

and other with

water.

The curd solution

turns yellow while

water remains

colourless.

-OH group is

present.


Strong iodine

followed by NaOHis added to 2 ml of

curd solution

Yellow crystalline

ppt. of iodine isformed.

Secondary

alcoholic grouppresent.


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PROCEDURE:

The following procedures are performed with SOYA BEANS

MILK CURD.

CARBONATE TEST OBSERVATION INFERENCE

2 ml of NaCO

solution is added to

2 ml of curd.

effervescence is

observed due

formation of CO.

-COOH group is

present.


Strong iodine

followed by NaOH

is added to 2 ml of

curd solution.

Yellow crystalline

ppt of iodoform is

formed.

Secondary

alcoholic group is

present .

FERRICCHLORIDE

SOLUTION


2 drops of ferric

chloride is added

to 2 tubes. One

with 2 ml of curd

and the other withwater

The curd solution

turns yellow while

water remains

colourless.

-OH group is

absent.


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PROCEDURE:

The following tests are performed with COCONUTS MILK

CURD.

CARBONATE

TEST


2 ml of

Nasolution is

added to 2 ml ofcurd.

Effervescence is

observed due to

evolution of .

-COOH group is

present.

FERRIC

CHLORIDE TEST


2 drops of ferric

chloride solution isadded to 2 test

tubes, one with 2

ml curd and the

other with water.

The curd solution

turns yellow whilewater remains

colourless.

-OH group is

present.


Strong iodinefollowed by NaOH

is added to 2 ml of

curd solution.

Yellow crystals ofiodoform is formed

Secondaryalcoholic group is

present.


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PROCEDURE :

the following tests are performed with OMFEDS MILK

CURD.

CARBONATE

TEST


2 ml of NaCOis

added to 2 ml of

curd.

Effervescence is

evolved due to

formation of

-COOH group is

present .

FERRIC

CHLORIDE TEST


2 drops of ferric

chloride is added

to test tubes , one

with 2 ml of curd

solution.

The curd solution

turns yellow while

water remains

colourless.

-OH group is

present.


Strong iodine

followed by NaOH

is added to 2 ml of

curd solution.

Yellow crystalline

ppt. of iodoform is

formed.

Secondary

alcoholic group is

present.


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CONTENTS

SL.NO. TOPIC PAGE NO.1. AIM OF THE

PROJECT

2. REAGENTS ANDAPPARATUS

REQUIRED3. PRINCIPLE

INVOLVED

4. PROCEDURE(COWSMILK, GOATS MILK,

SOYA BEANS MILK,

COCONUTS MILK,

OMFEDS MILK)

5. OBSERVATION

6. REACTIONSINVOLVED

7. RESULT ANDINFRENCE

8. CONCLUSION

9. PRECAUTIONS

10. BIBLIOGRAPHY


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OBSERVATION

REACTIONS INVOLVED:-

CARBONATE TEST:

() ()

FERRIC CHLORIDETEST:

CH() [(())]

IODOFORM TEST:

CH()


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RESULT AND INFERENCE :

ALL FIVE DIFFERENT SAMPLES OF CURD

CONTAIN LACTIC ACID

CONCLUSION


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LACTIC ACID:

It is the constituent of milk and hence its name is derivedfrom ( L.LACTIS= milk)

PROPERTIES :

Physical: lactic acid is colourless liquid, sour in taste with

melting point at 291K and of specific gravity of 1.25 and is

soluble in water , alcohol and ether.

Chemical: lactic acid molecule contains a secondary

alcoholic -COOH group , a carboxyl group as an -hydroxy

propionic acid with the chemical formula ()

Preparation:

1.By hydrolysis ofACETALDEHYDE CYANOHYDRINS2.B fermentation of molasses by micro-organisms

BACILLUS ACEDILACTI. They are optically active due to

the presence of central asymmetric carbon atom.it

occurs in isomers. Optically inactive -L.LACTIC ACID .

This form is found in sour milk and gastric juice .The

other two active forms are , Dextro- rotatory lactic acid

& laevo- rotatory lactic acid ( unstable at room

temperature).

Uses:


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1.In dairy products

2.As acidulant in beverages and candles

3.As a mordant

4.As a plasticizer

5.Calcium and iron lactates used in medicine


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PRECAUTIONS:-

The tst tube should be clean and dry. Only required amount of chemicals should

be added.

The chemicals should be handled carefully.


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BIBLIOGRAPHY

Comprehensive chemistry class XII. Chemistry Laboratory Manual by Laxmi

publication.

Modern College of Chemistry (II) by K.D.Sharma & J.Y.R. Sharma.

Documents

chemistry project class 12 on presence of acetic acid in samples of curd