concentration of KHP and the dependent variable is the factor being measured

Concentration of khp and the dependent variable is

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concentration of KHP and the dependent variable is the factor being measured, the concentration of NaOH. The control would be the indicator, phenolphthalein. Procedure and Materials
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Preparation of 0.1 M Sodium Hydroxide To make a 1 M solution, 3.9842g of NaOH was added to the 100 mL of boiled and cooled water in a volumetric flask. 10 mL of the original NaOH solution was taken and placed in a 100 mL volumetric flask and filled with deionized water to the marker, making a 0.1 M solution. (See parts 1 and 2 in Results section) Standardization of NaOH The amount of Potassium Hydrogen Phthalate to be transferred into a 250 mL Erlenmeyer flask with 25 mL of DI water was calculated using the following formula: Mass of KHP = Mass x Volume x Molecular weight 0.51055g of KHP was the idea mass of KHP to add to the solution (see part 3 in Results section). 0.5123g of KHP was added a 250 mL Erlenmeyer flask in trial one; 25 mL of DI water and 3 drops of the indicator phenolphthalein was also added to the flask. A clean 50 mL buret was mounted in a buret stand and cleaned using DI water and about 5 mL of the prepared NaOH solution. The NaOH solution was added to the buret and the initial volume was recorded. The NaOH was added to the KHP solution dropwise and the receiver was manually stirred. Titration was stopped once the receiving solution remained a faint pink for more than 15 seconds. The final volume was recorded. 0.5125 g of KHP was added to another Erlenmeyer flask with 25 mL of DI water and 3 drops of phenolphthalein. More NaOH solution was added to the buret and the initial volume was recorded. The solution was titrated until the faint pink color was permanent; the final volume was recorded. The rest of the NaOH solution was added to the buret and the initial volume was recorded. 0.5105 g of KHP was added to another Erlenmeyer flask with 25 mL of DI water and 3 drops of phenolphthalein. The solution was titrated until the faint pink color was permanent; the final volume was recorded. The average molarity of the NaOH was found and the percent error was determined. Results/ Discussion Part 1: Preparation of 1 M NaOH solution
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Number of Moles = Mass Molecular weight = Molarity · Volume Mass 39.97 g / mol = 1M · 0.1 L Theoretical mass of NaOH = 3.9842 g Part 2: Preparation of 0.1 M NaOH solution M 1 V 1 = M 2 V 2 (1 M) (V 1 ) = (0.1 M) (100 mL) 0.1 · 100 1 = 10 mL of original stock Part 3: Dried KHP Theoretical mass of KHP = Molarity · Volume · Molecular Weight = (0.1 M) (0.025 L) (201.22 g/mol) 0.51055 g of KHP I. Titration (Standardization of NaOH) Table 1 The above table shows the mass of KHP added to the Erlenmeyer flasks for titration for each trial. The table also displays the initial and final volumes of NaOH for each trial and the volume of NaOH used. The molarity of NaOH calculated from the amount of NaOH used in the titration is also shown for
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