1. Determination of Vitamin C in Grape Juice acid, which gives the characteristic citrus taste to various fruits and juices. HO HO HO OH OH O HO, HO CHO Citric acid Determination of ascorbic acid content by redox titration: -Indicator: starch - Volume of Indicator: 2 mL -* Volume of juice: 50 mL -*Dilute to approx. 50 mL - Titrant: Iodine (I2) -* Reaction (1:1 reaction between startch and Ascorbic acid): CHSO6(aq) + Iz(aq) → CH,O6(aq) + 21(aq) + 2H* (aq) Iodine is used to titrate vitamin C (ascorbic acid). When all the acid has been oxidized, the extra iodine reacts with the starch to produce a colored complex (blue similar to Iodine clock reaction). Determination of citric acid by acid/base titration: -Indicator: phenolphthalein - Volume of Indicator: 2-5 drops -*Volume of juice: 10 mL

1. Determination of Vitamin C in Grape Juice acid, which gives the characteristic citrus taste to various fruits and juices. HO HO HO OH OH O HO, HO CHO Citric acid Determination of ascorbic acid content by redox titration: -Indicator: starch - Volume of Indicator: 2 mL -* Volume of juice: 50 mL -Dilute to approx. 50 mL - Titrant: Iodine (I2) - Reaction (1:1 reaction between startch and Ascorbic acid): CHSO6(aq) + Iz(aq) → CH,O6(aq) + 21(aq) + 2H* (aq) Iodine is used to titrate vitamin C (ascorbic acid). When all the acid has been oxidized, the extra iodine reacts with the starch to produce a colored complex (blue similar to Iodine clock reaction). Determination of citric acid by acid/base titration: -Indicator: phenolphthalein - Volume of Indicator: 2-5 drops -*Volume of juice: 10 mL

Chemical Principles in the Laboratory

11th Edition

ISBN:9781305264434

Author:Emil Slowinski, Wayne C. Wolsey, Robert Rossi

Publisher:Emil Slowinski, Wayne C. Wolsey, Robert Rossi

Chapter24: The Standardization Of A Basic Solution And The Determination Of The Molar Mass Of An Acid

Section: Chapter Questions

Problem 3ASA: A 0.3012g sample of an unknown monoprotic acid requires 24.13mL of 0.0944MNaOH for neutralization to...

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