Chemistry Project

 Preface Guava is a sweet, juicy and light or dark green colored    fruit. It is cultivated in all parts of India. When ripe it  acquires yellow color and has a penetrating strong scent. The fruit is rich in vitamin C and minerals it is rich  source of oxalate and its content in the fruit varies during  different stages of ripening.

Obj ective of pro j ect    In this project, we will learn test the presence of oxalate ions in the guava fruit and how its amount varies during  different stages of ripening.

EXPERIMENT

 AIM T o

study the presence of oxalate ion content in guava fruit at different stages of ripening.

REQUIR MENTS 100

ml of measuring flask, pestle and mortar, beaker, titration flask, funnel, burette, weight box, filter paper, dilute H 2SO4 ,  N\10 KMnO4   solution and guava fruits at  different stages of ripening.

THEORY  Oxalate ions are extracted from the fruit by boiling pulp with dil. H 2SO4. Then oxalate ions are estimated  volumetrically by the solution with standard KMnO 4  solution.

PROCEDURE 1. Weigh

50.0 g of fresh guava and crush it to a fine  pulp using pestle-mortar.

2. Transfer the crushed pulp to a beaker and add about  50 ml dil. H 2SO4 to it. Boil the contents for about  10 minutes.

3. Cool and filter the contents in 100 ml measuring    flask. Make the volume up to 100ml by adding  distilled water. 4. Take 10 ml of the solution from the measuring flask  into a titration flask and add  10ml of H 2SO4 to it.  Heat the mixture to about 6 0Û C and titrate it against 

 N/ 10 KMnO4 solution taken in burette. The end point  is appearance of permanent light-pink color. 5. Repeat the above experiment with 5 0.0 g of 1 , 2 and 3 old guava fruit.

OBSERV  A TIONS = 5 0.0 g 

Weight of guava fruit taken each time

Volume of guava extract taken in each titration =  Normality of KMnO 4 

solution Burette reading

10.0

ml 

1 / 10

=

Concordant volume of N/10KMnO4 solution used

Sr.no

Guava extract  from

1.

Fresh guava

X ml

2.

One day old guava

X1ml

3.

Two days old guava

X2ml

4.

Three days old guava

X3ml

Initial

Final

C ALCULA TIONS 1.

for fresh guava  N V  = 1

1

(Guava extract)

N 2V 2 (KMnO 4 solution)

 N  ×10 = 1 / 10 × x = 1 / 10 × 1

 Normality of oxalate, N  = x/ 100 = 1

Strength of oxalate in fresh guava extract  = Normality × Eq. mass of oxalate ion = x/ 100 × 44g/liter of diluted extract. =

× 44g/liter of diluted extract.

2. for one day old guava  N V  = 1

1

(Guava extract)

N 2V 2 (KMnO 4 solution)

 N  ×10 = 1 / 10 × x = 1 / 10 × 1

 Normality of oxalate, N  = x/ 100 = 1

Strength of oxalate in one day old guava extract  = Normality × Eq. mass of oxalate ion

= x/ 100 × 44g/liter of diluted extract. =

× 44g/liter of diluted extract.

3. for two day old guava  N V  = 1

1

(Guava extract)

N 2V 2 (KMnO 4 solution)

 N  ×10 = 1 / 10 × x = 1 / 10 × 1

 Normality of oxalate, N  = x/ 100 = 1

Strength of oxalate in two day old guava extract  = Normality × Eq. mass of oxalate ion = x/ 100 × 44g/liter of diluted extract. =

× 44g/liter of diluted extract.

4. for three day old guava  N V  = 1

1

(Guava extract)

N 2V 2 (KMnO 4 solution)

 N  ×10 = 1 / 10 × x = 1 / 10 × 1

 Normality of oxalate, N  = x/ 100 = 1

Strength of oxalate in three day old guava extract 

= Normality × Eq. mass of oxalate ion = x/ 100 × 44g/liter of diluted extract. =

× 44g/liter of diluted extract.

C h  he   em   mi  is   st   tr  r  y     p  p r  ro   o j  e  ec   ct   t  To study the presence of oxalate ion content in guava   fruit at different stages of ripening.

C ounselor:

  Mrs. Preeta S Kumar

Devised By: Nishant Dwivedi (XII)

 Session: 2009-2010

 Acknowledgment   I  give

my humble thanks to my inspiration Mr. S.P  T iwari.  I  also thanks my and owe my head for giving their precious time and guiding me with the inspiration to forge ahead in times of my detachment from the pro j ect. T o my special friends it my special thanks to help me and making me able to complete my pro j ect with their restless effort and  contri bution. T his pro j ect is a combined and restless contri bution and devotion of my friends, parents, concerned teacher working on the pro j ect.

 I t

is a special thanks to a special friend for the help.

 I t

is the inspiration of Mr. S.P  T iwari, my parents, and friends. heartily thanks to god for being with me all the time.

 I 

BIBLIOGRAPHY From the under given sources I have arranged the information 1. Compressive Chemistry Practical XII 2. Internet

C ontents  Acknowledgment   Preface Obj ective O f Pro j ect   Aim  Procedure  Requirements T heory Observations Calculations