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Postlab Report for Colligative PropertiesChemistry 112 Lab Section 005October 14, 2014A.The research questions for this lab are:1.What is the % dissolved solids in my potato?2.What is the freezing temperature for pure lauric acid?3.What is the MM of the unknown organic acid?B.Observations and Results.TablesTable 1. Osmosis Demonstrated by Changes in Potato Mass.SolventInitial mass of potato (g)Final mass of potato (g)% Change in mass of potato (%)Direction of solvent flow (intoor out of potato)Distilled water24.10024.7202.5726Into potato9% Glucose11.78711.8710.71265Into potato17% Glucose28.05527.261-2.8302Out of potatoCalculations for table 1:% Change in mass of potato:Distilled water potato: 24.720−24.10024.100∗100=2.57269% Glucose potato: 11.871−11.78711.787∗100=0.7126517% Glucose potato: 27.261−28.05528.055∗100=−2.8302Table 2. Summary of Data & Calculations to Determine the MM of the Unknown Solute.Mass of lauric acid (g)8.016Mass of unknown organic acid (g)1.005Freezing temperature of pure lauric acid (°C)44.0Freezing point of the unknown-lauric acid mixture (°C)41.0Freezing point depression, ΔT (°C)3.0Molality (m)0.77Moles of unknown (mol)0.0062Molecular mass (MM) of unknown (g/mol)1.6 x 102Calculations for table 2 are on the attached data analysis. C.Complete claims for each of the research questions above.
1.The % dissolved solids in my potato is 9.148 %.2.The freezing temperature for pure lauric acid is 44.0 °C.3.The MM of the unknown organic acid is 1.6 x 102g/mol.D.Evidence Compose and attach a statement of the evidence you have to support each of the claims youmade in Section C. You will need to describe some theoretical background about osmosis andfreezing point depression. Specifically using your data, (you must use actual numbers and resultsfrom your experiment) explain why your claims are correct. You may refer to other sections of
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Chemistry, Freezing-point depression, Lauric acid, pure lauric acid