# Refer to table 1 equation absorbance at chosen

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Refer to Table 1.Equation: (absorbance at chosen wavelength)*(dilute concentration of CV)/(stock CV concentration)Procedure/MethodsList of Materials/Reagents:25 µM crystal violet solution (CV), 50 mL0.02 M sodium hydroxide solution (NaOH), 30 mLColorimeterSerological pipet, 10 mLProcedure:Absorbance Values For Crystal Violet1.Obtain a sufficient amount of stock crystal violet solution.2.Turn on the colorimeter and let it warm up, setting it to a wavelength of 565 micrometers.3.Using a pipet, add the volumes of CV to five test tubes specified in Table 1.4.Using a pipet and distilled water, dilute each test tube to 10.0 mL.5.Attach the colorimeter to a graphing program and calibrate it using a cuvette with distilled water.6.Record the absorbance values for each of the five concentrations in a data table.7.Graph the results.
Reaction of Crystal Violet with Sodium Hydroxide1.Obtain a sample of crystal violet solution and a sample of hydroxide solution.2.Using a pipet, add 5 mL of CV solution to a test tube.3.Add 5 mL of hydroxide solution to the same test tube using a pipet, quickly stoppering it, shaking it, and adding it to a cuvette that is placed in the colorimeter.4.Record the values every three seconds for ten minutes.5.Graph the results.Hypothesis/PredictionThe order of reaction with respect to crystal violet will be first order. Data
Calculationsrate = k [CV+][OH-] k = 0.001357 s-1from slope of graphOrder of reaction with respect to crystal violet: first order [ln(concentration) being most linear]Rate= k’ [CV+]nk’=k [OH-]m0.001357= k[OH-]k=0.001357/.01k=0.1357Rate=0.1357 [OH-] [CV+]AnalysisDiscussionPostlab Questions:
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