WEDNESDAY APRIL 6, 2011

Today was a late arrival day! We started off by reviewing the answers to the Reading Sheet for Chapter 11.1-2. The answers are:

1. B

2. A

3. C

4. B&C

5. A&D

6. C

7. A

8. B

9. D&C

10. False; M is often not equal to the coefficient

11. The order of this reaction is 1. You determine this by using trials 1&3: [A] doubles as the rate doubles

12. k=about 6.2/s (From trial 1:1.24=k(0.2)^1)

13. 2

14. With respect to A: 1 With respect to B: 2 Overall order: 3

After that, we spent the rest of the class period review problems that have to do with reaction rates. We reviewed how to write the rate law equation. We then learned how to calculate the rate constant, otherwise known as K. To determine the value of K, you simply divide the initial rate by all of the other individual concentrations in that trial multipled together (don't forget to multiple each concentration by it's order of reaction number). After you calculate the rate constant (K), you are able to predict the initial rate when given the concentrations which is another new topic learned in class. The equation for predicting the initial rate is: Rate=K(concentration1*order of reaction)(concentration2*order of reaction)(concentration3*order of reaction). An example of all of these topics learned can be found in our packet on page 2 #4. The problem is listed below:

After we did problem number 4, we turned to page 3 to try a problem on our own. The problem lists a balanced equation. Below the balanced equation, there is a chart of collected data which shows the different trials listed with the concentration of the compounds along with the Rate in mol/L/s. You are to determine the order of the reaction along with the overall order of the reaction which is found by looking for patterns in the chart like we did in class. Once there is a pattern found, you are able to determine the power for that compound which will be the order of the reaction. After you find the order of the reaction for all of the compounds, you add them together to calculate the overall order of the reaction. Next you are to write the rate law, which goes along with the order of the reacitons. An example of a rate law is shown below (Rate=K*[F2]*K[ClO2]^2). After you write the equation for the rate law you are to calculate the rate constant. Again, the example for the rate constant is shown below (K=1.20x10^-3/(.10)(.010^2). The constant for this problem is calculated to be 120. Lastly, you are to calculate the rate of the reaction at the tim when [F2]=.010 mol/dm^3 and [ClO2]=.020 mol/dm^3. To figure out how to do this, you simply take the rate constant (120) and multiply it by (.010) and (.020^2) to get 48.80x10^-4 as your rate.

That was all we had time for today, remember there is a Web Assign due Friday!

--Katie Jennings