1. 1 Question of the Day 4-3 Day 3

2. 2 Question of the Day 4-4 Day 4 For a reaction involving a single reactant A, the following data were obtained. Rate (mol/L∙min) 0.0200.0160.013 0.010 [A] (mol/L) 0.1000.0900.080 0.070 a. The order of the reaction in A is __________. b. The rate law for the reaction is...

3. 3 Question of the Day: 1. What are the three options when combining reactants? 2. An equilibrium reaction is NOT a ____________________. Period 1 4-4 day 4 Period 3 4-3 day 3

4. http://chemconnections.org/Java/equilibriu m/index.html http://www.chem.iastate.edu/group/Greenbo we/sections/projectfolder/animations/equilv pBr2V8.html Equilibrium

5. D. Example of system reaching equilibrium N 2 O 4(g) ⇄ 2 NO 2(g) at 100 °C [N 2 O 4 ][NO 2 ] → [N 2 O 4 ][NO 2 ] Exp #10.1000.000 → Exp #20.0000.100 → Exp #30.100 → 0.0400.120 0.0140.072 0.0700.160 Equilibrium

6. What happened to the concentrations of each substance during the experiments? –Changed so that NO 2 always has higher [ ] at equilibrium –Compare chemical equation to equilibrium [ ] Chemicals with higher coefficients have higher [ ] Chemicals with lower coefficients have lower [ ] Equilibrium

7. A.What is the use of K C ? –Tells extent of reaction –Determines how much product could form B.What is the formula to determine K C ? aA (g) + bB (g)  cC (g) + dD (g) [C]c [D]d [A]a [B]b Kc = Equilibrium

8. C.What happens to K C if the reaction is reversed? –Inverts K c to 1/K c –Flip products and reactants in K c expression D.What importance does phase have in the K C calculations? –Only gases or solutions are used –Solids and pure liquids maintain same concentrations over time Equilibrium

9. E.How are K C expressions written? 2 SO 3(g) ⇄ 2 SO 2(g) + O 2(g) Kc = [SO2]2 [O2] [SO3]2 Homogeneous Equilibrium = all the same phase Equilibrium

10. E.How are K C expressions written? CuO (s) + H 2(g) ⇄ Cu (s) + H 2 O (g) Kc = [H2O] [H2] Heterogeneous Equilibrium = different phases Equilibrium

11. F.How is K C calculated in a problem? The following system reaches equilibrium at 500 °C in a 5.0 L container. Calculate K C if there are 2.0 mol NH 3(g), 2.0 mol HCl (g), and 1.0 mol NH 4 Cl (s) at equilibrium. NH 4 Cl (s) ⇄ NH 3(g) + HCl (g) Kc =[NH3][HCl] =2 mol 5 L [] [] 2 mol 5 L =[0.4][0.4] K c = 0.16 Equilibrium

12. LAB Packets due tomorrow!

13. 13 Question of the Day: Calculate the K C for O 2(g) + N 2(g) ⇄ 2 NO (g) when the equilibrium concentrations are [N 2(g) ] = [O 2(g) ] = 0.040 M, and [NO] = 0.00035 M. Day 5 4-5

14. 14 Question of the Day: For the equilibrium described by: PCl 5 (g) ↔ PCl 3 (g) + Cl 2 (g) K c equals 35 at 487°C. If the concs. of the PCl 5 and PCl 3 are 0.015 M and 0.78 M, respectively, what is the conc. of the Cl 2 ? Day 6 4-8

15. LABS: Presentations AND Lab Reports: Due Friday 4-12!!!

16. Assignment Review section 18.3 AND read the section on Le Chatelier’s principle. Complete #s 25-32 on page 620. - Due Tuesday 4-9

17. Day 6 3-12 http://wps.prenhall.co m/esm_brown_chemist ry_9/2/660/169060.cw/i ndex.html Homework # 2 Chapter 15 – w/ discussion partner – show me successful screen (100%)