(10 pts) Rate law for second order. (Basically M&S P28.24) As in class, start 22 eq. 25 and show how to get to equation 27. 2. (10 pts) The decomposition dimethyl ether results in methane, carbon monoxide and hydrogen gases. This gas phase reaction was studied by studying the time it took for the total pressure to double based on the initial pressure of the ether (presumably in a constant volume container). From the following data, i) determine the order of the reaction (rate law)* and ii) its rate constant. Initial P (torr) 28 58 150 171 261 321 394 422 509 586t (s) 1980 1500 900 824 670 625 590 508 465 4843. (10 pts) M&S P29.15 (Reaction of ethyl acetate) 4. (10 pts) Arrhenius Problem. Calculate the energy of activation for the following data for the decomposition of N2O5-> N2O4 + ½ O2, T (K) 270 370 470 570 670k x 109 (cm6 mol-2 s-1) 9.12 4.67 3.28 2.75 2.495. (10 pts) M&S P28.17 – Parallel First Order Reactions* What I did (and there are other approaches) was to first figure out what extent of decomposition (I called it a) gave 2X the original pressure. Then I used the rate laws for -(dA/dt) = kAn, where n was likely to be half an integer, i.e., 0, ½, 1, 3/2, 2, etc. and A is the pressure of the system. I plotted the data for each order and eventually, found that one of these exponents fit the data very well over the entire concentration range. (Note: From Excel, you can plot things from rows or columns, if you like columns, you can paste special -> transpose).
MoreChem
ical Equilibria Chapt 26 Dependsonedition office3 5WedHRs
I FreeEnergy and Equilibrium constants
A FreeEnergy
1 Extentof reaction 5 lowercase Xi for A B
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heChatelier‘s Principle equilibriumshifts to less gaseous
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So it depends howyour operationworks fixedPorv which one You use
Chem 3433-63342, Physical Chemistry 1
Problem Set #10
When possible, use the values for constants from our text. If you get them from other sources (if they are not in the book) cite where you got them from.
Do, but do not hand in P26.1, P26.2 to get you started.
1. (10 pts) Rate law for second order. (Basically M&S P28.24)
As in class, start 22 eq. 25 and show how to get to equation 27.
2. (10 pts) The decomposition dimethyl ether results in methane, carbon monoxide and hydrogen gases. This gas phase reaction was studied by studying the time it took for the total pressure to double based on the initial pressure of the ether (presumably in a constant volume container). From the following data, i) determine the order of the reaction (rate law)* and ii) its rate constant.
Initial P (torr) 28 58 150 171 261 321 394 422 509 586
t (s) 1980 1500 900 824 670 625 590 508 465 484
3. (10 pts) M&S P29.15 (Reaction of ethyl acetate)
4. (10 pts) Arrhenius Problem. Calculate the energy of activation for the following data for the decomposition of N2O5 -> N2O4 + ½ O2,
T (K) 270 370 470 570 670
k x 109 (cm6 mol-2 s-1) 9.12 4.67 3.28 2.75 2.49
5. (10 pts) M&S P28.17 – Parallel First Order Reactions
* What I did (and there are other approaches) was to first figure out what extent of decomposition (I called it a) gave 2X the original pressure. Then I used the rate laws for -(dA/dt) = kAn, where n was likely to be half an integer, i.e., 0, ½, 1, 3/2, 2, etc. and A is the pressure of the system. I plotted the data for each order and eventually, found that one of these exponents fit the data very well over the entire concentration range.
(Note: From Excel, you can plot things from rows or columns, if you like columns, you can paste special -> transpose).