Determine the difference in freezing temperatures \u0394T between the pure lauric

Determine the difference in freezing temperatures δt

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Determine the difference in freezing temperatures, ΔT, between the pure lauric acid (t1) and the mixture of lauric acid and benzoic acid (t2). Use the formula, ΔT = T1- T2.2.Calculate molality (m), in mol/kg, using the formula, Δt = Kf• m (Kf= 3.9°C-kg/mol for lauric acid). 3.Calculate moles of benzoic acid solute, using the answer in Step 2 (in mol/kg) and the mass (in kg) of lauric acid solvent.4.Calculate the observedlmolecular weight of benzoic acid, in g/mol. Use the original mass of benzoic acid fromthe Data and Calculations table, and the moles of benzoic acid you found in the previous step.5.Determine the expectedmolecular weight for benzoic acid from its formula, C6H5COOH.6.Calculate the percent error.7. Include a full error analysis in your lab report.
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DATA AND CALCULATIONS Mass of lauric acid ________ g Mass of benzoic acid ________ g Freezing point of pure lauric acid ________  ° C Freezing point of the benzoic acid- lauric  acid mixture ________  ° C Freezing temperature depression,  t ________  ° C Molality, m ________ mol/kg Moles of benzoic acid ________ mol Molecular weight of benzoic acid (experimental) ________ g/mol Molecular weight of benzoic acid (accepted) ________ g/mol Percent error % 100 Expected Expected - Observed = Error % x ________ %
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  • Fall '16
  • Algebra, Freezing-point depression, Lauric acid

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