b Click on the Linear Regression button c Now click and drag the mouse over the

B click on the linear regression button c now click

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temperature decreases rapidly (before freezing occurred). b.Click on the Linear Regression button, c.Now click and drag the mouse over the next linear region of the curve (the gently sloping section of the curve where freezing took place). d.Click again. The graph should now have two regression lines displayed. e.Choose Interpolate from the Analyze menu. Move the cursor to the point of intersection of the two lines; you will know if the cursor is over the intersection when the temperature readings displayed in the interpolate box are the same. This is the freezing point of the benzoic acid-lauric acid mixture. f.Record the freezing point in your data table. 14. Print a graph showing both trials. . DATA TABLE Mass of lauric acid (g) Mass of benzoic acid (g) Freezing temperature of pure lauric acid (°C) Freezing point of the benzoic acid-lauric acid mixture (°C)
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Computer 4 4 - 4 Advanced Chemistry with Vernier DATA ANALYSIS 1. Calculate molality (m), in mol/kg, using the formula t= Kfm. The Kfvalue for lauric acid is 3.9°Ckg/mol. 2. Calculate moles of benzoic acid solute, using the molality and the mass (in kg) of lauric acid solvent. 3. Calculate the experimentalmolecular weight of benzoic acid, in g/mol. 4. Determine the acceptedmolecular weight of benzoic acid from its formula, C6H5COOH. 5. Calculate the percent discrepancy between the experimental and accepted values.
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  • Fall '10
  • JAMESE.KUSTERER
  • Mole, Freezing-point depression, Lauric acid

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