1. Kinetics Lab A little help to get you started

2. PreLab Q1 Hint: The reaction time is NOT the rate. Time = sec Rate = mol/L sec To find the rate of each of the three reactions, divide the molarity, 0.002M by the time for each reaction

3. PreLab Q1b Use the Differentiated Rate equations to determine the orders of each reactant. #1 rate = k[.04] x [.04] y #2 rate = k[.08] x [.04] y solving for x; x = 1 PreLab Q1c: solve for y using #1 and #3

4. PreLab Q2 Solve the same as Q1, except the rate is given. Once you have determined the overall rate equation, substitute any trial into the equation and solve for k Use dimensional analysis to determine the units for k

5. PreLab Q3 Save one entire page in your composition book for this. We will cover the concept of temperature dependence on Monday. Part 3 of the lab allows us to prove this assumption in the lab

6. PostLab Part 1 Using your data from part 1, calculate the average mass of one drop of water Then… Mass 1 drop 1.00ml 1L = 1.00g 1000ml This will give you the vol of 1 drop of water

7. PostLab Part 2 Determine the mol S 2 O 3 2- In the lab, you used 1 drop of S 2 O 3 2- So… 1 drop Q1 L.001mol = 1 drop 1 L = mol S 2 O 3 2- Molarity

8. PostLab Part 2 Determine the mol of BrO 3 - This is done by linking S 2 O 3 2- to BrO 3 - by using equations #1 and #3 on the front page of the lab. Because neither equation has both species, we will link the two using I 2. mole S 2 O 3 2- 1 mol I 2 1mol BrO 3 - = 2mol S 2 O 3 2- 3 mol I 2 = mol S 2 O 3 2- Answer from last slide

9. PostLab Part 2 Calculate the [BrO 3 - ] mol BrO 3 - 1 drop = 12 drops L = M BrO 3 - Answer from last slide Answer from Part 1 Total volume after mixing

10. PartLab Part2 Calculate the Reaction Rates M BrO 3 - = Avg time (sec) Perform this calculation for each of the seven trial. (Data Table page 79) Answer from last slide Average time for each trial in part 2

11. PostLab 2B…finally Now you must calculate the molarity of each species in the rxn: [I - ] [BrO 3 - ] [H + ] Use your dilution equation: M 1 V 1 = M 2 V 2 [I - ].01M (2drops) = M (12 drops) =.00167M [BrO 3 - ].04M (2drops) = M (12 drops) =.0067M [H + ].10M(2 drops) = M (12 drops) =.0167M This example is for trial #1. You must complete a similar set of calculations for each of the seven trials

12. PostLab 2C Once you have all your concentrations and rates calculated, now you can solve for the orders of each of the three reactants, just like you did in PreLab Q1 Rate = k[I - ] x [BrO 3 - ] y [H + ] z Email me with questions or stop in Monday before school