Name:
College ID:
Thomas Edison State College
General Chemistry II with Labs (CHE-122)
Section no.:
Semester and year:
Laboratory Assignment for Module 3: Reaction Rates
(eScience Lab 4 [16])
Table 1. 10 mL Undiluted IKI and 5 mL 3% H2O2
Water displaced in milliliters |
Time in seconds |
2 mL |
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4 mL |
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6 mL |
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8 mL |
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10 mL |
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12 mL |
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14 mL |
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16 mL |
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18 mL |
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20 mL |
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22 mL |
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Table 2. 10 mL 0.5–1.0% IKI and 5 mL 3% H2O2
Water displaced in milliliters |
Time in seconds |
2 mL |
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4 mL |
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6 mL |
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8 mL |
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10 mL |
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12 mL |
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14 mL |
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16 mL |
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18 mL |
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20 mL |
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22 mL |
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Table 3. 10 mL 0.5–1.0% IKI and 5 mL 2.25% H2O2
Water displaced in milliters |
Time in seconds |
2 mL |
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4 mL |
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6 mL |
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8 mL |
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10 mL |
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12 mL |
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14 mL |
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16 mL |
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18 mL |
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20 mL |
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22 mL |
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III. CALCULATIONS (20 POINTS)
Table 1: 10 mL Undiluted IKI and 5 mL 3% H2O2
Slope:
Inverse Slope:
Table 2: 10 mL 0.5–1.0% IKI and 5 mL 3% H2O2
Slope:
Inverse Slope:
Table 3:10 mL 0.5–1.0% IKI and 5 mL 2.25% H2O2
Slope:
Inverse Slope:
Order of H2O2:
Order of IKI:
Rate law constant:
*Show Calculations and Include Graphs
IV. RESULTS (15 POINTS)
Overall rate law:
1. How many grams of IKI (iodine-potassium iodide; molar mass = 166.0 g/mol) would it take to obtain a 100.0 mL solution of 0.300 M IKI? How many grams of IKI would it take to create a 100.0 mL solution of 0.600 M IKI? (6 points)
2. What is the molarity of 100.0 mL of a 3.0% H2O2 (mass/volume) solution? What is the molarity of 100.0 mL of a 2.25% H2O2 (mass/volume) solution? (6 points)
3. When finding the order of H2O2, why was Trial 1 and Trial 3 used? (6 points)
4. When finding the order of IKI, why was Trial 1 and Trial 2 used? (6 points)
5. How does temperature affect the reaction rate? Explain in terms of the collision theory.
(6 points)
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Name:
College ID:
Thomas Edison State College
General Chemistry II with Labs (CHE-122)
Section no.:
Semester and year:
Laboratory Assignment for Module 4: Equilibrium Constants
(eScience Lab 5 [17])
Table 1. Equilibrium Constants Data
Syringe Reading, mL |
pH after each 0.5 mL increment |
Color Observations |
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III. CALCULATIONS (15 POINTS)
Volume of NaOH when solution turns dark pink/orange:
Volume of NaOH at the equivalence point (the point on the graph midway between the vertical rise; see Lab 7 [19], Figure 2):
pH at the equivalence point (should be approximately 8–9):
Volume of NaOH at equivalence point:
Volume at half-equivalence point:
pH at the half-equivalence point:
pH = pKa at this point
Ka (equilibrium constant):
pKa = –log Ka
Show calculations
IV. RESULTS (20 POINTS)
Experimental Ka of acetic acid:
Theoretical Ka of acetic acid:
1. Compare your experimental value for the equilibrium constant to the theoretical value. Do you notice any variation? If so, why? (10 points)
2. Write the dissociation of acetic acid, HC2H3O2.(10 points)
3. Write the equilibrium expression for acetic acid. (10 points)
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Name:
College ID:
Thomas Edison State College
General Chemistry II with Labs (CHE-122)
Section no.:
Semester and year:
Laboratory Assignment for Module 5: Standardization of a Solution
(eScience Lab 7 [19])
Mass of beaker:
Mass of beaker and citric acid:
Mass of beaker and citric acid (after cooling):
Volume of NaOH:
Table 1. Trial 1 Data
Syringe Reading, mL |
Citric acid added, mL |
pH |
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Table 2. Trial 2 Data
Syringe Reading, mL |
Citric acid added, mL |
pH |
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III. CALCULATIONS (15 POINTS)
Include your graphs with your report.
Mass of citric acid:
Moles of citric acid:
(MW = 192.0 g/mol)
Molarity of citric acid:
(volume of solution = 100 mL)
Trial 1 equivalence point:
Trial 2 equivalence point:
Show calculations
IV. RESULTS (20 POINTS)
Molarity (Trial 1):
Molarity (Trial 2):
Average Molarity:
1. Use Figure 3 in your laboratory manual to determine which combination of acids and bases provide the most distinguishable equivalence point. Which combination is the most difficult to determine an equivalence point? (10 points)
2. There are many different primary standards that could be used in a standardization titration. What are the criteria of a primary standard?(10 points)
3. Potassium hydrogen phthalate (KHP; KHC8H4O4) is a good primary standard. If it took 20.0 mL of NaOH to react with 15.5 mL of 0.600 M KHP solution, what is the molarity of the NaOH solution? (10 points)
KHC8H4O4 + NaOH → KNaC8H4O4 + H2O