Once the solution has been completely dissolved add 3

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50mL flask use a water bottle to help dissolve the solid. Once the solution has been completely dissolved add 3-4 drops of indicator to each flask. After this check the burette to insure that it will not leak by adding deionized water to the top and allowing it to run out as shown by the instructor. Once it has been checked carefully add 50mL of the 0.040 M NaOH solutions that was made previously in part A to the burette. Don't waste time trying to get to the 0.0 mark on the burette. Instead record the exact volume to two decimal spaces in the data section. Titrate the sample in the 50mL flasks slowly until a pale pink color remains for at least 3 seconds. Be careful to not exceed the endpoint or a dark pink color will appear and have to do trial number 3. Receive instructor approval on the color for at least one sample before moving on. Record the final volume of the NaOH. Do not add more NaOH to the burette between trials it is not necessary. Use the final volume from the first trial as the initial volume for the second trial. Thenuse the volume of NaOH and grams of KHP to calculate the molarity of the NaOH solution by
using the equationMNaOHVNaOH=MHClVHCl. After finding the molarity record the concentration of the standardized NaOH solution in the manual. The molarity found will be used in part C and D. Once this is complete continue to part C titration of a carbonated beverage. Stepone of part C is to obtain 20mL of soda and record the brand in the data table. Then take a pipetteto get a drop of Sprite and drop it on a piece of pH paper and record the pH in the data section. Once finding the pH use it to evaluate what the concentration of +¿H¿in the Sprite should be. This will be confirmed with your standardized NaOH. Clean out two 50mL flasks and label it trial 1 and 2. Take a clean 10mL graduated cylinder and measure between 2.8-3.2mL of Sprite. Then add 20mL of deionized water to make the titration easier. Once that is done fill the burette with 50mL standardized NaOH and record the initial volume in the data table. Use the equationH3A(aq)+3NaOH(aq)→ Na3A(aq)+3H2O(l)to calculate the concentration of acid in the Sprite sample. After part C is complete start on part D titration of citric acid. First obtain a clean 50mL flasks. Then weigh out 0.05g of citric acid. After that dissolve the sample in 20ml of water and add 3-4 drops of phenolpthalein. Then fill a burette with 50mL of standardized NaOH, record theinitial volume in the data table. Titrate the citric acid to a light pink color; it should maintain the pink color for at least 30 seconds. If it fades to colorless then add another drop of sodium hydroxide to the sample. Once that is done record the final volume of NaOH in the data table. Repeat another trial if you have time too. Data/Results: In part A: preparation of NaOH the concentration and volume of the stock solution used and the volume after dilution and the final concentration. The concentration of the stock solution is 2.5m of NaOH. The volume of the stock solution used was 3.2mL. After dilution the volume

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