University:
Texas State University
Course:
CHEM 1141 | General Chemistry Laboratory I
Academic year:

2024
Views:

351

Pages:

3
Author:

Riya J.

Kinetics Pre Lab Assignment Purpose: Determine the kinetic orders of H2O2 and Fe3+ using different concentrations of these species. A balanced reaction with these species is : Fe(NO3)3 + 2H2O2 ⟶ O2 + 2H2O + Fe(NO3)3. One of the products is elemental oxygen, O2, and it is monitored in situ by using LabQuest pressure probe to record the pressure over time. Three different concentrations of the H2O2 and Fe3+ will be mixed together, and using the time-based pressure values, the initial rates of every reaction will be found. Additionally, the order of reaction will be found and is then used to find the empirical rate law of the reaction will be determined. Objectives: 1) Performing three reactions with Fe(NO3)3 and H2O2 in a 125 mL Erlenmeyer flask using different volumes of each reactant 2) Monitoring elemental oxygen using a pressure probe with LabQuest 3) With Logger Pro 3.15, Excel, or LabQuest determining the initial rate of each of the reactions 4) Comparing initial reaction rates with initial concentration of every reaction 5) Determining the empirical rate law for the reaction Materials: USB drive Vernier LabQuest 2 Vernier pressure probe Syringe 125 mL Erlenmeyer flask 30 or 50 mL beaker (x3) 1 mL volumetric pipette Pipette bulb Compounds: 0.5 M Fe(NO3)3 3% (0.921 M) H2O Deionized H2O Chemical Hazards: - (Fe(NO3)3) can cause irritation if it touches, eyes or skin - Hydrogen peroxide is dangerous if ingested or touches eye as it can cause skin burns or eye damage Physical Hazards: - Risk of rupture due to pressure - Broken glassware Equation: Fe(NO3)3 + 2H2O2 ⟶ O2 + 2H2O + Fe(NO3)3 Outline: - Gather total of 3 solutions that is used during run 1-2 - Transfer 0.5 M Fe(NO3)3 from stock solution into clean beaker - Transfer H2O2 from stock solution to beaker - Add water to beaker - Prepare LabQuest 2 for collection - Plug into outlet - Plug in pressure probe - “Sensors” - “Data collection” - “Mode” - “time based” - 480 s - Begin run 1 - Transfer Fe(NO3)3 into flask - Swirl flask and stopper flask using rubber stopper - Take H2O2 solution - Collect data Run 2: - Pipet Fe(NO3)3 solution and deionized water into flask Take H2O2 Collect data Inject H2O solution and close stopcock After 8 minutes vent the flask Calculate molarities Run 3: - Pipet Fe(NO3)3 solution and deionized water into flask - Collect data - Open stopcock and inject H2O solution Stop after 8 minutes and remove stopcock Calculate molarities