Presence of Oxalate Ions in Guava: A Chemistry Investigatory Project by Aman Ahuja, Summaries of Performing arts

Download Presence of Oxalate Ions in Guava: A Chemistry Investigatory Project by Aman Ahuja and more Summaries Performing arts in PDF only on Docsity! North hills international school By Aman Ahuja Presence of oxalate ions in guava A Chemistry investigatory Project Certificate This is certify that Aman Ahuja of class 12-A science has Successfully completed the project on “Oxalate ions in guava” Under the guidance of Vijay teacher during the year 2023-2024 In partial fulfillment of Chemistry project by C.B.S.E AIM- To study the presence of oxalate ions in guava fruit at different stages of ripening. Introduction guava is a common sweet fruit found in India and many other places around the world. Guavas are plants in the Myrtle family (Myrtaceae) genus Psidium (meaning "pomegranate" in Latin), which contains about 100 species of tropical shrub. On ripening it turns yellow in color. Rich in vitamin C, this fruit is a rich source of oxalate ions whose content varies during the different stages of ripening. Guavas have a pronounced and typical fragrance, similar to lemon rind but less in strength. Why oxalate It is a carboxylic acid, primarily found in plants and animals. It is not an essential molecule and is excreted from our body, unchanged. Our body either produces oxalate on its own or converts other molecules like Vitamin C to oxalate. External sources like food also contribute to the accumulation of oxalate in our body. The oxalate present in the body is excreted in the form of urine as waste. Too much of oxalate in our urine results in a medical condition called hyperoxaluria, commonly referred to as kidney stones. Diet is looked upon as a preventive measure in addition to medication to treat kidney stones. Theory Oxalate ions are extracted from the fruit by boiling pulp with dilute H2SO4. The oxalate ions are estimated volumetrically, by titrating the solution with KMnO4 solution. A reagent, called the titrant, of a known concentration (a standard solution) and volume is used to react with a solution of the analyte or titrand, whose concentration is not known. Using a calibrated burette or chemistry pipetting syringe to add the titrant, it is possible to determine the exact amount that has been consumed when the endpoint is reached. The endpoint is the point at which the titration is complete, as determined by an indicator. This is ideally the same volume as the equivalence point. The volume of added titrant at which the number of moles of titrant is equal to the number of moles of analyte, or some multiple thereof (as in polyprotic acids). In the classic strong acid-strong base titration, the endpoint of a titration is the point at which the pH of the reactant is just about equal to 7, and often when the solution takes on a persisting solid colour as in the pink of phenolphthalein indicator. Precaution 1.There should be no parallax while taking measurements. 2.Spillage of chemicals should be checked. 3.Avoid the use of burette having a rubber tap as KMnO4attacks rubber. 4. In order to get some idea about the temperature of the solution touch the flask with the back side of your hand. When it becomes unbearable to touch, the required temperature is reached. 5.Add about an equal volume of dil. H2SO4 to the guava extract to be titrated (say a full test tube) before adding KMnO4. Read the upper meniscus while taking burette reading with KMnO4 solution. 7. In case, on addition of KMnO4 a brown ppt. appears, this shows that either H2SO4 has not been added or has been added in insufficient amount. In such a case, throw away the solution and titrate again. Observation Calculation i. A}For raw guava N1V1 = N2V2 ii. ➔N1 x 10 = (1/10) x132 iii. ➔1/10 x Normality of oxalate = (x/100) = strength of oxalate in fresh guava extract = normality x Eq. mass of oxalate ion iv. = 1.32/100 x 44g/litre of diluted extract v. = 0.581 g L-1 2) vi. B]For semi ripened guava (1 day old). Strength of oxalate in one day old guava extract vii. = (1.37 /100) x 44g/litre of diluted extract viii. = 0.603 g L-1 ix. c) For ripened guava x. Strength of oxalate in fresh guava extract = ( 1.39/100) x 44g/litre of diluted extract = 0.612 g L- Results A]The normality of oxalate ions of; • Fresh guava solution is = 1.32 ml • Semi-ripen guava solution is = 1.37 ml • Ripened guava solution is = 1.39 ml B] The strength of oxalate ions of • Fresh guava solution is = 0.58 ml • Semi-ripened guava is = 0.60 ml • Ripened guava is = 0.61 ml Conclusion The content of oxalate ions in guava was found to be 59.67 per cent, which is close to the literature value of 60 percent. It was also noticed that the content of oxalic ions grows with ripening of guava.