"A pH sensor is used in order to monitor pH as titration is done. The region of most rapid pHchange is thus used to determine the equivalence point. Again for the morality of H3PO4, thevolume of NaOH titrant is used at the equivalence point. OBJECTIVES:? Here pH Sensor is used to monitor pH when the titration of phosphoric acid is done ina soft drink. ? Using the titration equivalence point, determine the molarity of H3PO4. MATERIALS: 1. Computer2.0.050 M NaOH3.Vernier computer interface4.various soft drinks, decarbonated 5. Logger Pro 6. distilled water 7. Vernier pH Sensor 8. ring stand 9. 50 ml burette 10. utility clamp 11. 100 ml graduated cylinder 12. magnetic stirrer (if available) 13. 250 ml beaker 14. stirring barPROCEDURE: 1. A graduated cylinder should be used to measure 40 ml of a decarbonated colabeverage as well as 60 ml of distilled water in a 250 ml beaker2. A beaker is placed on a magnetic stirrer along with a stirring bar. If a magnetic stirreris not available then a stirring rod can be used for the titration. 3. Now pH sensor is connected to the computer interface. Therefore, computer isprepared for data collection by opening the file with Vernier folder of Logger Pro.4. A utility clamp is used to suspend a pH Sensor on a ring stand. The pH sensor ispositioned in the HCI solution as well as its position is adjusted so that it does not getstruck by the stirring bar.5.Take 50 ml buret and then rinse it with a few ml of the 0.050 M NaOH solution. 6. Now the process of titration can be performed. If a person manipulates as well asreads the buret, the process becomes more faster, where as another person operatesthe handled and enters the volume. 7. To find the equivalent point, the data on the graph of pH vs. volume is examined, thatis 0.5 ml increment of volume that resulted in the largest increase in pH. As theexaminer line is moved, the pH as well as volume values of the data point are shownon the right side of the graph.8. Find the NaOH volume and record after the 0.5ml addition producing the largest pHincrease. Result:After we conducted several tests and experiments it was clear that most of the cold drinkscontains glucose, alcohol,, sucrose, phosphate, carbon dioxide etc. Therefore, all the cold drinks are acidic in nature. When we compared the pH value of different brands of colddrinks we found that some of them are highly acidic and some are lesser acidic. Affects of acid content in soft drinks on humans: Acidity is the most important factor in the preservation of soft drinks. Low pH greatlyincreases the effects of heat treatment while also acting as an additional barrier to the growthof microorganisms. The pH level of most soft drinks is below 4.0. The great majority ofheterotrophic bacteria are unable to grow at such low pH values. However, fungal growth ispossible at low pH levels. Chilled storage is often used to extend the open shelf life of fruitjuices. Most spoilage yeasts and molds are able to grow at 5°C, albeit slowly. Some molds,such as Penicillium spp., can grow in chilled juices at 0°C. Lactic acid bacteria gradually loseviability in chilled juices. The use of oxygen-impermeable packaging cans double the shelflife of juices from 35 to 65 days. It is often recommended that, after opening, products shouldbe chilled and consumed within 3 days. Most spoilage incidents caused by yeasts are controlled by preservative systems.However, certain yeast species show resistance, especially to weak-acid preservatives. Thesestrains belong to the fermentative yeast species Saccharomyces cerevisiae,Schizosaccharomyces pombe, Zygosaccharomyces spp., and Dekkera spp.Zygosaccharomyces bailii is able to grow in the presence of both 60% w/v glucose andpreservatives far in excess of the legal limits in Europe. Resistance to sorbic and benzoicacids by Z. bailii may be caused by reduced uptake combined with metabolism of thepreservatives. Other preservative-resistant spoilage yeasts include Issatchenkiaorientalis (Candida krusei), Pichia membranifaciens, Schizosaccharomyces pombe,and Saccharomyces cerevisiae. "