Laboratory Assignment for Module 3: Reaction Rates
(eScience Lab 4 [16])

Table 1. 10 mL Undiluted IKI and 5 mL 3% H₂O₂

Table 2. 10 mL 0.5–1.0% IKI and 5 mL 3% H₂O₂

Table 3. 10 mL 0.5–1.0% IKI and 5 mL 2.25% H₂O₂

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

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 = pK_a  at this point

K_a (equilibrium constant):

pK_a = –log K_a                                    

Show calculations

IV.  RESULTS (20 POINTS)

Experimental K_a of acetic acid:

Theoretical K_a 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

Table 2. Trial 2 Data

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