Description 1. Read the lab in lab manual pages 231-237 and fill out data table by completing the c ...

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Description 1. Read the lab in lab manual pages 231-237 and fill out data table by completing the calculations using the raw data. Table 1. Raw and Processed Data for the Thermodynamic Dissolution of Borax Experiment Trial one Trial Two Trial One Trial Two Trial One Trial Two Trial One Trial Two Temperature of solution (ºC) 22 22 30 30 40 40 49 49 Concentration of HCl (M) 0.283 0.283 0.283 0.283 0.283 0.283 0.283 0.283 Volume of Borax Solution (mL) 5 5 5 5 5 5 5 5 Initial Buret Reading (mL) 32.6 13.2 36.3 39 40.1 45 43.1 40 Final Buret Reading (mL) 34.5 15.5 39 41.6 45 49 48.4 48 Volume of HCl (mL) Moles of HCl (moles) Moles of Borate (moles) Concentration of Borate (M) Ksp Average Ksp ? G (kJ/mol) ? H (kJ/mol) ? S (J/mol K) 2. Complete the following calculations – For each trial: – Calculate moles HCl titrated – Calculate moles borate ion – Calculate concentration borate ion – Calculate Ksp at the given T and average – Calculate your ?G values ? Class data (at home) on Excel – Do the same for each data point (moles HCl, moles borate ion, conc borate ion, Ksp) – Make a plot of ln(Ksp) vs 1/T for all of the data – Determine ?H and ?S from this graph – Calculate ?G using equations A and B (see lab manual) 3. Complete the Results section • A 2nd Excel worksheet “Calculation of Ksp”. This should include the following columns: o Volume HCl titrated in L for trial 1 o Volume HCl titrated in L for trial 2 o Moles of Borax for trial 1 o Moles of Borax for trial 2 o Concentration of borax for trial 1 o Concentration of borax for trial 2 o Ksp calculated from concentration of borax for trial 1 o Ksp calculated from concentration of borax for trial 2 o Average Ksp • A 3rd Excel worksheet “Calculation of Thermodynamic Values” showing the calculated results for each student in the class – each in a separate row. This should include the following columns: o Natural log of average Ksp o Temperature (converted to Kelvin) o Reciprocal Temperature (1/T) o Slope of ln(Ksp) vs. 1/T graph o Intercept of ln(Ksp) vs. 1/T graph o Gibbs Free Energy calculated using equation A: ?G = -RT ln Ksp o Average of ?G o Enthalpy (found from slope) o Entropy (found from intercept) o Gibbs Free Energy calculated using equation B: ?G = ?H - T?S o Average of ?G • A 4th, 5th, and 6th Excel sheet “Graphs” showing a graph of ln(Ksp) vs 1/T, ?G vs T (using Equation A to calculate ?G), and ?G vs T (using Equation B to calculate ?G) • 1-5 Sentence summary of your results at the end of the calculation section Example: – ____ g (or mL) of Reagent A were reacted with _____ g (or mL) of Reagent B until a precipitate formed/gas evolved/color change occurred. Observations were made and data were collected. Table 1 represents _____. Table 2 represents _____. Figure 1 represents _____. Figure 2 represents ____. 4. Answer the following discussion questions ? Compare your two calculated delta G values; do they agree? Based on your values, is the dissolution of borax spontaneous? ? Why is it necessary to ensure that there was always some solid borax in the solution? ? What was the Ksp value for your temperature? What does this say about the solubility of borax at this temperature? Compare this to the Ksp values at other temperatures and make a statement regarding the effect of temperature on solubility. If your results do not match what you expected, analyze sources of error. ? Literature values for enthalpy and entropy of the dissolution of borax in water are 110 kJ/mol and 380 J/mol*K respectively. Do your values agree? Calculate your percent error and discuss sources of experimental error. You assumed that delta H and delta S are constant over the temperature range studied. Are they? 5. Write a conclusion paragraph answering the following questions: ? Re-state the purpose of the experiment – For example: “The purpose of the experiment was to ___________” ? How did you attempt to meet the purpose? – For example: “This was done by___________” ? Was the purpose met? – For example: “The purpose was/was not met and…” ? Was the actual outcome close to the anticipated outcome? – For example: “…the actual outcome was/was not near the anticipated outcome” ? Why or why not? What errors did you specifically experience in this experiment? – For example: “The reason for the difference between the actual and anticipated outcomes is that during the experiment errors A and B occurred…” ? What are some future improvements to this experiment?