Once calculated, these results can be analyzed and will either validate or refute my hypothesis. Introduction (Library Research): Ascorbic acid (vitamin C) is found in orange juice. In this experiment, orange juice made from the concentrate was measured for decreases/increases of off-flavours (furfural and α-terpineol) and for decreases/increases of ascorbic acid. Sodium hydroxide (NaOH) as well as hydrochloric acid (HCl) were added during separate trials to change the PH in the orange juice. An increase of PH from 3.2 to 4.2 enabled the protection of ascorbic acid levels, without increasing the levels of other enzymes.
The mixture was refluxed to avoid evaporation while it boiled for 30 minutes. After 30 minutes the mixture was cooled and then filtered through fluted filter paper into a 250ml round bottom flask. The methyene chloride dissolved the trimystrin and would pass through the filter paper leaving the other nutmeg solids behind. The solution was then distilled to get rid of the methlyene chloride and isolate the trimyristin. Methlyene chloride was a good solvent in this case because its boiling point is 40 degrees C and will boil off before the trimyristin which has a boiling point of 56-57 degrees C. Finally acetone was added to wash the crystals and the solution was vacuum filtered.
Tannins, which are organic compounds that can bind to alkaloids such as caffeine, are going to be taken out of the tea water using sodium carbonate. The sodium carbonate is a base, which will convert the acidic tannins into sodium salts that are highly soluble in water. Isolating the caffeine will continue once methylene chloride is added to the remaining tea solution, which increases the solubility of the caffeine. Methylene chloride can be evaporated quickly leaving the caffeine to be purified by sublimation. Materials and Methods: The tea solution was obtained when a tea bag was placed in boiling water and its liquid mix was carefully squeezed into a beaker; and eventually placed into a test tube.
Aim: | The aim of this experiment is to analyse a sample of vinegar and determine it’s concentration. | | | Hypothesis: | It’s expected that the aceatic acid will have the concentration of 0.1mol as this is the molarity of the NaOH as they have a 1:1 ratio of moles as it states in their chemical equations. | | | Apparatus: | * 1 x retort stand * 1 x retort burette clamp * 1 x burette * 1 x pipette * 1 x glass funnel * 2 x Conical Flasks * Sheet of filter paper * 200mL of 0.1 mol L-1 NaOH * 200mL of acetic acid of unknown concentration | | | Procedure: | 1. WARNING: Wear safety glasses and gloves! 2.
956). To isolate caffeine from various substances requires different methods based on the composition of the solution it is being extracted from. High pressure processing is a new method that extracts caffeine from tea leaves and has been shown to have an advantage such as shorter extraction times (Nature.com). Similarly, the process of extracting and sublimating this ingredient from tea leaves was performed in the following experiment and its concentration was determined. Methods When the prepared tea solution has cooled down to room temperature, transfer 10-mL of tea into two centrifuge
Acid Base Titration Purpose: The purpose is to calculate the molarity of a NaOH solution by titrating the base with 5mL of standard HCl solution in each trial. By adding the base with unknown molarity to the acid with 0.10M the molarity of NaOH can be calculated. The base, NaOH, helps bring the pH of the acid, HCl, closer to seven, which neutralizes it. When using the buret the amount of NaOH used is able to be determined. Then by writing a balanced chemical equation and using the titration formula, Nb+Ma+Va=Na+MbVb , the molarity is able to be determined.
Task 2 Extended Experimental Investigation of Vitamin C Contents Abstract 3 Introduction 3 Aim 4 Hypothesis 4 Materials 4 Titration Planning and Results 5 Procedure 5 Volume of Potassium Iodate added to Titrate Juices. 6 Vitamin C Concentration 6 Discussion 7 Conclusion 7 Bibliography 8 Abstract The experiment was conducted to find whether Vitamin C was preserved and protected more in a citrus such as squeezed Orange juice rather than squeezed Kiwi Fruit Juice, An Apple Juice in a Tetra Pack and squeezed Apple Juice. The experiment was done using the Redox Titration method. This resulted in the Tetra Pack having lost the least amount of Vitamin C with a difference of 12.47mg/100ml degrading. The Orange Juice which was predicted to have the lowest loss of Vitamin C had a difference of 15.64mg/100ml which was less than the other squeezed juices.
Isolation of Caffeine from Tea CHEM243A 2-23-11 Abstract: The purpose of this experiment was to isolate caffeine from a tea bag. Once isolated, the caffeine was purified using sublimation. The percent recovery was calculated to be 83.3%. The melting point of the original substance was 51ºC-139ºC. Since it was inaccurate, the melting point of another group’s sample was recorded.
* Secondly you have to add five drops of phenolphthalein the test tube which you are using. * Then measure out 5 cm of milk using a syringe or a measuring cylinder, and then add this to the test tube. * After this measure out 7 cm of sodium carbonate solution using a different measuring cylinder or a syringe and then add this to the test tube, which will make the solution turn pink. * Next you will have to place a thermometer in the test tube, but you will have to be careful as the experiment could fall over. * Then you will have to put the test tube in a water bath and leave it until the contents reach the same temperature as the water bath.
Introduction Caffeine is a molecule that is similar to the purine base xanthine. The only recognizable difference is that caffeine has a methyl group. The goal of this experiment is to isolate caffeine from tea leaves, and then purify it by using sublimation. This experiment will use three techniques, extraction, recrystallization and melting point determination. A sequence of extractions has to be done to take out the other components from tea.