{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

# 5 - Elbel Brittany Homework 5 Due noon Inst J A Holcombe...

This preview shows pages 1–3. Sign up to view the full content.

Elbel, Brittany – Homework 5 – Due: Feb 20 2006, noon – Inst: J A Holcombe 1 This print-out should have 24 questions. Multiple-choice questions may continue on the next column or page – find all choices before answering. The due time is Central time. 001 (part 1 of 1) 10 points A certain reaction has a K c = 9 . 0 at 35 C. A(g) + B(g) * ) 2 C(g) We have a mixture in which [A] = 2 M, [B] = 4 M, and [C] = 1.5 M. Which of the following is true of the mix- ture? 1. The reaction will go to the right. correct 2. More A and B will be formed to achieve equilibrium. 3. The reaction will go to the left. 4. The mixture is at equilibrium. Explanation: K c = 9 . 0 [A] = 2 M [B] = 4 M [C] = 1 . 5 M Q = [C] 2 [A] [B] = (1 . 5 M) 2 (2 M) (4 M) = 0 . 28 < K c = 9 . 0 Therefore, equilibrium will shift to the right. 002 (part 1 of 1) 10 points At 990 C, K c is 1.6 for the reaction CO 2 (g) + H 2 (g) * ) H 2 O(g) + CO(g) If 4.0 mol of CO, 3.0 mol of H 2 O, 2.0 mol of H 2 , and 1.0 mol of CO 2 are placed in a 5.0 liter container and allowed to reach equilibrium at 990 C, which response includes all of the following statements that are correct, and no others? I) The concentration of H 2 will be greater than 0.40 mol/L. II) The concentration of H 2 O will be less than 0.60 mol/L. III) The concentration of CO will be less than 0.80 mol/L. IV) The concentration of CO 2 will be greater than 0.20 mol/L. 1. I, II, III, and IV correct 2. I and IV only 3. I and II only 4. III only 5. I, II, and IV only Explanation: [H 2 O] ini = 3 . 0 mol 5 . 0 L = 0 . 6 M [CO] ini = 4 . 0 mol 5 . 0 L = 0 . 8 M [CO 2 ] ini = 1 . 0 mol 5 . 0 L = 0 . 2 M [H 2 ] ini = 2 . 0 mol 5 . 0 L = 0 . 4 M Q = [H 2 O] [CO] [CO 2 ] [H 2 ] = (0 . 6 M) (0 . 8 M) (0 . 2 M) (0 . 4 M) = 6 > K c = 1 . 6 Therefore equilibrium will shift to the left, in- creasing [CO 2 ] and [H 2 ] and decreasing [H 2 O] and [CO]. 003 (part 1 of 1) 10 points CS 2 and Cl 2 react according to the following equation CS 2 (g) + 3 Cl 2 (g) * ) S 2 Cl 2 (g) + CCl 4 (g) . When 1.0 mole of CS 2 and 3.00 moles of Cl 2 are placed in a 2.00 liter container and allowed to come to equilibrium, the mixture is found to contain 0.25 moles of CCl 4 . What is the amount of Cl 2 at equilibrium? 1. 0.25 mol Cl 2 2. 0.75 mol Cl 2

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Elbel, Brittany – Homework 5 – Due: Feb 20 2006, noon – Inst: J A Holcombe 2 3. 2.25 mol Cl 2 correct 4. 0.50 mol Cl 2 5. 2.75 mol Cl 2 Explanation: Initially, [CS 2 ] = 1 mol 2 L = 0 . 5 M [Cl 2 ] = 3 mol 2 L = 1 . 5 M CS 2 (g)+ 3 Cl 2 (g) * ) S 2 Cl 2 (g)+ CCl 4 (g) 0.5 M 1.5 M 0 M 0 M - x M - 3 x M x M x M 0 . 5 - x 1 . 50 - 3 x x x At equilibrium, [CCl 4 ] = x = 0 . 25 mol 2 . 0 L = 0 . 125 M mol Cl 2 = [1 . 50 M - 3(0 . 125 M)](2 . 00 L) = 2 . 25 mol 004 (part 1 of 3) 10 points Consider the reaction HCHO(g) * ) H 2 (g) + CO(g) 1.0 mol of HCHO, 1.0 mol of H 2 and 1.0 mol of CO exist in equilibrium in a 2.0 L reaction vessel at 600 C. a) Determine the value of the equilibrium constant K c for this system. 1. 2.0 2. 1.0 3. K c cannot be determined for gaseous equilibria. 4. 0.50 correct 5. Some other value Explanation: The expression for K c here is K c = [H 2 ] [CO] [HCHO] , so we need to know the equilibrium concen- trations of each of the species. Since each is 1 . 0 mol 2 . 0 L = 0 . 50 M, then K c = [0 . 50] [0 . 50] [0 . 50] = 0.50 005 (part 2 of 3) 10 points 2.0 moles of HCHO and 1.0 mol of CO are then added to this system.
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern