hw4solution_pdf - So (dds785) Homework 4 Sutcliffe (52440)...

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

View Full Document Right Arrow Icon

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

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: So (dds785) Homework 4 Sutcliffe (52440) 1 This print-out should have 25 questions. Multiple-choice questions may continue on the next column or page find all choices before answering. Refer to the notes published on Blackboard regarding Lewis acids and bases. 001 (part 1 of 2) 10.0 points Consider the reaction 22 . 1 kcal + PCl 5 (g) PCl 3 (g) + Cl 2 (g) How does the equilibrium shift if the vol- ume of the container is decreased? 1. You must know the actual volume to tell. 2. left correct 3. right 4. no net shift Explanation: A volume decrease is the same as a pressure increase. The equilibrium will shift to the side with the fewest gas moles which is to the left. Also, the value of Q would be greater than K so the reaction would shift left. 002 (part 2 of 2) 10.0 points How does the equilibrium shift when temper- ature is increased? 1. It depends on whether it is on the Kelvin or Celsius scale. 2. left 3. no net shift 4. right correct Explanation: Because the reaction is ENDOthermic, an increase in temperature would push the reaction forward. The equilibrium constant would increase as a result. 003 10.0 points Each of the following reactions occurs in a 1.0 liter container and is at equilibrium. A(g) + B(g) 2 C(g) a) 3 A(g) + B(g) 2 D(g) b) 2 A(g) 2 C(g) + D(g) c) If the volume in each container is reduced by one-half, will the Q c be greater than, less than, or equal to the K c for each reaction? The answers are in order of a, b, and c. 1. equal; greater; less 2. greater; greater; less 3. less; greater; equal 4. equal; less; greater correct 5. greater; greater; equal 6. equal; greater; greater 7. greater; equal; less 8. less; less; greater 9. equal; less; less 10. greater; less; equal Explanation: 004 10.0 points Note: Some of you may need to consider the definition of BOND ENERGY to answer this question. Predict whether the equilibria I) CH 4 (g) + H 2 O(g) CO(g) + 3 H 2 (g) , H = +206 kJ II) CO 2 (g) + 2 NH 3 (g) CO(NH 2 ) 2 (s) + H 2 O(g) , H =- 90 kJ will shift toward products or reactants with a temperature increase. 1. Unable to determine 2. I shifts toward products and II shifts to- ward reactants. correct So (dds785) Homework 4 Sutcliffe (52440) 2 3. Both I and II shift toward products. 4. Both I and II shift toward reactants. 5. I shifts toward reactants and II shifts toward products. Explanation: If a reaction is exothermic, raising the tem- perature will tend to shift the reaction toward reactants; whereas if the reaction is endother- mic, a shift toward products will be observed. Reaction I is endothermic (+ H ); raising the temperature should favor the formation of products. Reaction II is exothermic; raising the temperature should favor the formation of reactants....
View Full Document

This note was uploaded on 10/25/2010 for the course CH 302 taught by Professor Holcombe during the Fall '07 term at University of Texas at Austin.

Page1 / 7

hw4solution_pdf - So (dds785) Homework 4 Sutcliffe (52440)...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online