User:Melissa Novy/Notebook/CHEM-572/2013/02/19

Objectives

• Grind 100Ag-LMT made on 2013/02/05 into a fine powder.
• Make PLA2002D + 5 wt% 100Ag-LMT film.
• Make PLA2002D + 5 wt% LMT film.

PLA2002D Films

• The protocol on 2013/02/06 was used to make the films.
• Each film contained 5 wt% of 100Ag-LMT or LMT for one gram of PLA2002D.

• PLA2002D + 5 wt% LMT film
  • Theoretical mass PLA2002D: 1 g
  • Theoretical mass LMT: 0.05 g
  • Actual mass PLA2002D: 1.009185 g
  • Actual mass LMT: 0.05060 g

• PLA2002D + 5 wt% 100Ag-LMT film
  • Theoretical mass PLA2002D: 1 g
  • Theoretical mass 100Ag-LMT: 0.05 g
  • Actual mass PLA2002D: 1.01686 g
  • Actual mass 100Ag-LMT: 0.05062 g
  • Final mass of PLA2002D + 5 wt% 100Ag-LMT: 0.97 g

• Actual content of silver in 0.5 g PLA2002D + 5 wt% 100Ag-LMT:
  • Please refer to data from the entries on 2013/02/05 and 2013/02/13 for the data listed below.

  0.00622 g AgNO3 × (1 mol AgNO3/169.87 g AgNO3) × (1 mol Ag+/1 mol AgNO3) = 3.66 × 10-5 mol Ag+
  [Ag+] in 5 mL 100Ag-LMT filtrate was 0.000253614 M
  0.000253614 M Ag+ × 0.005 L = 1.2681 × 10-6 mol Ag+
  Therefore, 3.66 × 10-5 mol Ag+ − 1.2681 × 10-6 mol Ag+ = 3.53 × 10-5 mol Ag+ was exchanged into 100Ag-LMT.

  0.05 × 0.5 g PLA2002D + 5 wt% 100Ag-LMT = 0.025 g 100Ag-LMT
  (3.53 × 10-5 mol Ag+) ÷ (0.05062 g 100Ag-LMT) = x mol Ag+ ÷ (0.025 g 100Ag-LMT)
  4.47 × 10-8mol Ag+ in 0.025 g 100Ag-LMT of 0.5 g PLA2002D + 5 wt% 100Ag-LMT film

ISE Study of PLA2002D + 5 wt% 100Ag-LMT

• Calculations:
  • To determine maximum [Ag⁺] possible, assume that all Ag⁺ leaches out of solution.
  • The solution contained 50 mL pure H₂O and 1 mL ionic strength adjuster. The recommended ratio of solution to ionic strength adjuster is 50 mL to 1 mL. Then, 0.50 g of film was added to the solution.

  (4.47 × 10-8mol Ag+0 ÷ 0.051 L = 8.76 × 10-7 M or 0.876 μM

• Protocol
  1. Pour 50 mL pure H₂O into a clean, dry 250-mL Erlenmeyer flask and add 1 mL of 5 M KNO₃.
  2. Measure the conductivity of the solution with the ISE.
  3. Place the film into the flask, swirl, and measure the conductivity.
  4. Wait 30 min, then measure the conductivity again.
  5. Repeat the above step 5 more times.