DAT General Chemistry - Problem Drill 14: Chemical Equilibrium

Similar documents
MCAT General Chemistry Discrete Question Set 20: Kinetics & Equilibrium

A. Correct. You successfully completed the stoichiometry problem. B. Incorrect. There are 2 moles of AgCl produced for each mole of CaCl 2 reacted.

AP Chem Chapter 12 Notes: Gaseous Equilibrium

A. Correct! You successfully completed the stoichiometry problem.

(A) Composition (B) Decomposition (C) Single replacement (D) Double replacement: Acid-base (E) Combustion

AP CHEMISTRY NOTES 8-1 CHEMICAL EQUILIBRIUM: AN INTRODUCTION

H 2 O (l) H + (aq) + OH (aq)

Common Ion Effect on Solubility

GASEOUS EQUILIBRIUM CH. 12 EQUILIBRIUM

Chapters 10 and 11 Practice MC

A.P. Chemistry. Unit #11. Chemical Equilibrium

A. Incorrect. Check the sum of elements of the same type on both sides of the equation. B. Correct. You have balanced the equation correctly!

January 03, Ch 13 SB equilibrium.notebook

Chapter 15 Chemical Equilibrium

UNIT 11 Practice Test Page 1 of 13 Equilibrium

E. Incorrect. Look carefully there is a statement that is true about weak acid dissociation.

CHEMICAL EQUILIBRIUM. I. Multiple Choice 15 marks. 1. Reactions that can proceed in both the forward and reverse directions are said to be:

REACTION EQUILIBRIUM

3 Chemical Equilibrium

Worksheet 21 - Le Chatelier's Principle

Solubility Equilibrium

Chapter 15: Chemical Equilibrium. Chem 102 Dr. Eloranta

BIOB111_CHBIO - Tutorial activity for Session 6:

Dr. Zellmer Chemistry 1220 Monday Time: 18 mins Spring Semester 2019 February 4, 2019 Quiz III. Name KEY Rec. TA/time

11 Equilibrium. S T A T I O N 1 K e q E X P R E S S I O N S S T A T I O N 2 G R A P H S. South Pasadena Honors Chemistry 11 Equilibrium Period Date

Chapter 15 Equilibrium

Chem 116 POGIL Worksheet - Week 9 Equilibrium Continued Introduction to Acid-Base Concepts

Chapter 14: Chemical Equilibrium. Mrs. Brayfield

Chapter 6: Chemical Equilibrium

EXAM 2 Free Response. K c. C. Calculate Q and indicate which direction the reaction will proceed as it moves towards equilibrium (2 points)

UNIT II - REVIEW EQUILIBRIA. Part I - Multiple Choice. 1. In which of the following does the entropy decrease?

which has an equilibrium constant of Which of the following diagrams represents a mixture of the reaction at equilibrium?

Chemical Equilibrium

Worksheet 18 - Equilibrium. Balance the following reaction, and use it to answer the following 8 questions:

15.1 The Concept of Equilibrium

Intermolecular Forces 2 nd Semester Review Questions and Problems

Chapter 15 Chemical Equilibrium

Chemical Equilibria 2

Unit 4: Acid/Base I. abinotes. I) Introduction to Acids and Bases What is an acid?

CHEM 112 Final Exam. Practice Test Solutions

CH302 Spring 2009 Practice Exam 1 (a fairly easy exam to test basic concepts)

Chemical Equilibrium Basics

Unit 3: Chemical Equilibrium Chemistry Write balanced chemical equations for each of the following. Pay close attention to the physical states!

Chemistry 12. Tutorial 5 The Equilibrium Constant (K ) eq

3 A (aq) + 2 D (aq) 4 C (g) + B (s) + 2 E (l)

Ch 15 Chemical Equilibrium STUDY GUIDE Accelerated Chemistry SCANTRON. Name /98

Acid-Base Titration Solution Key

Equilibrium Unit. Terminology. Terminology 11/04/2018. Chemistry 30 Ms. Hayduk

Aqueous Solutions and the Concept of ph

The. Equilibrium. Constant. Chapter 15 Chemical Equilibrium. The Concept of Equilibrium. The Concept of Equilibrium. A System at Equilibrium

CHEMpossible. Final Exam Review

Chemistry 12 April 2004 Provincial Examination

Chemical Equilibrium

Chp 13, 14, 15 SHOW ALL WORK AND CIRCLE FINAL ANSWERS. a) 1 only b) 2 only c) 3 only d) 1 and 2 only e) 1, 2, and H 2

Chemical Equilibrium. Many reactions are, i.e. they can occur in either direction. A + B AB or AB A + B

Solubility Equilibrium. Solutions. Dissociation Equations. April/May Chemistry 30

Solubility Equilibria

Write a balanced reaction.. then write the equation.. then solve for something!!

Chapter 15 Chemical Equilibrium. Equilibrium

IMPORTANT NOTE : any numbers to the left of the decimal in ph calculation do not count in significant figures for logarithms.

Experiment #8. LeChatelier s Principle

Chemical Equilibrium Practice Problems #2

Equilibrium. Slide 1 / 27. Slide 2 / 27. Slide 3 / 27. PART A: Introduction and Ice Tables EQUILIBRIUM

AP Chemistry. Le-Chatlier's Principle. Slide 1 / 27 Slide 2 / 27. Slide 4 / 27. Slide 3 / 27. Slide 5 / 27. Slide 6 / 27

1. (3) The pressure on an equilibrium mixture of the three gases N 2, H 2 and NH 3

Collision Theory. Collision theory: 1. atoms, ions, and molecules must collide in order to react. Only a small number of collisions produce reactions

aa + bb ---> cc + dd

*VI-1 C NC II-2 C NC V-2 C NC **VI-2 C NC II-3 C NC V-3 C NC IX-1 C NC IV-1 C NC VII-1 C NC IX-2 C NC IV-2 C NC VII-2 C NC V-1 C NC VIII-1 C NC

Chemical Equilibrium. A state of no net change in reactant & product concentrations. There is a lot of activity at the molecular level.

CHEMISTRY 12 EQUILIBRIUM PROPERTIES & ENTROPY AND ENTHALPY WORKSHEET CHEMISTRY 12 EQUILIBRIUM PROPERTIES WORKSHEET

For the reaction: A B R f = R r. Chemical Equilibrium Chapter The Concept of Equilibrium. The Concept of Equilibrium

Part One: Solubility Equilibria. Insoluble and slightly soluble compounds are important in nature and commercially.

1. Opp. Khuda Baksh Library, Ashok Rajpath, Patna House no. 5A/65, Opp. Mahual Kothi, Alpana Market, Patna

1 A. That the reaction is endothermic when proceeding in the left to right direction as written.

U N I T T E S T P R A C T I C E

Chapter 16 - Principles of Chemical Equilibrium

Equilibrium. What is equilibrium? Hebden Unit 2 (page 37 69) Dynamic Equilibrium

Review Unit #11. Review Unit # H 2 O (g) + CO (g) H 2(g) + CO 2(g) H>1

Notes: Acids and Bases

Chapter 15 Equilibrium

1.0 L container NO 2 = 0.12 mole. time

Chapter 16, Thermodynamics: Entropy, Free Energy, and Equilibrium

Chapter 10 Homework Answers

Page 1. Spring 2002 Final Exam Review Palmer Graves, Instructor MULTIPLE CHOICE

Chemistry 12 April 2001 Provincial Examination

Balance the following equation: Fe + O 2 Fe 2 O 3. Please complete your warm-up on a scratch piece of paper and turn it into the basket.

3. Indicate the mass action expression for the following reaction: 2X(g) + Y(g) 3W(g) + V(g) a) [X] 2 [Y][W] 3 [V] [W] 3 [V] [X] 2 [Y] [3W][V] [2X][Y]

Chemical Equilibrium

1. Describe the changes in reactant and product concentration as equilibrium is approached.

Lecture 5. Percent Composition. etc. Professor Hicks General Chemistry II (CHE132) Percent Composition. (aka percent by mass) 100 g.

CHEMISTRY Midterm #2 October 26, Pb(NO 3 ) 2 + Na 2 SO 4 PbSO 4 + 2NaNO 3

Equilibrium Practice Test

Name: Name: Page 1 of 6

Final Exam Review-Honors Name Period

Chemistry 122 (Tyvoll) EXAMINATION II KEY November 4, 2005

Chapter 15 Equilibrium

The 5 th planet in our solar system, Jupiter. The Mass Action Expression describes a system undergoing a chemical change.

Reaction Quotient. Initial M M M Initial M M M

Chapter 12: Chemical Equilibrium The Extent of Chemical Reactions

Introduction to Thermochemistry. Thermochemistry Unit. Definition. Terminology. Terminology. Terminology 07/04/2016. Chemistry 30

Transcription:

DAT General Chemistry - Problem Drill 14: Chemical Equilibrium Question No. 1 of 10 Instruction: (1) Read the problem statement and answer choices carefully () Work the problems on paper as needed (3) Question 1. What is the equilibrium constant for N O 4 (g) NO (g) if the equilibrium concentrations are: [N O 4 =4.7 10 - M and [NO =1.41 10 - M? Question #01 (A) 0.330 (B) 3.00 (C) 0.660 (D) 0.0050 (E) 0.00470 A. Incorrect Remember that when writing equilibrium constant expressions, the products are over the reactants with the balanced equation coefficients as the exponents. B. Incorrect Remember that when writing equilibrium constant expressions, the products are over the reactants with the balanced equation coefficients as the exponents. C. Incorrect Remember that when writing equilibrium constant expressions, the products are over the reactants with the balanced equation coefficients as the exponents. D. Incorrect Remember that when writing equilibrium constant expressions, the products are over the reactants with the balanced equation coefficients as the exponents. E. Correct. You correctly calculated the equilibrium constant. N O 4 (g) NO (g) [N O 4 eq = 4.7 10 - M [NO eq = 1.41 10 - M? [ NO [ N O 4 ( 1.41 10 ) 4.7 10 0.00470

Question No. of 10 Instruction: (1) Read the problem statement and answer choices carefully () Work the problems on paper as needed (3) Question : The reaction quotient for a system is 7. 10. If the equilibrium constant is 6, which way will the reaction proceed to reach equilibrium? Question #0 (A) To the right (B) To the left (C) It is at equilibrium (D) Not enough information (E) None of the above A. Incorrect. If the reaction quotient is too big, the top of the fraction (the products) needs to decrease. B. Correct. If the reaction quotient is too big, the top of the fraction (the products) needs to decrease. C. Incorrect. If the reaction quotient is too big, the top of the fraction (the products) needs to decrease. D. Incorrect. If the reaction quotient is too big, the top of the fraction (the products) needs to decrease. E. Incorrect. If the reaction quotient is too big, the top of the fraction (the products) needs to decrease. Q = 7. 10 6 Which way will reaction go? If Q = K, it s at equilibrium If Q > K, there are too many products and too few reactants If Q < K, there are too few products and too many reactants Q > K. There are too many products. The reaction will shift to the left to reduce the products and make more reactants.

Question No. 3 of 10 Instruction: (1) Read the problem statement and answer choices carefully () Work the problems on paper as needed (3) Question 3: What is the correct equilibrium constant expression for the following reaction? NO Cl (g) NO (g) + Cl (g) Question #03 [ NO [ Cl [ NO Cl (A) (B) [ NOCl (C) [ NO [ Cl [ NO [ Cl (D) [ NOCl (E) [ NO [ Cl [ NOCl [ NO [ Cl A: Incorrect. B: Incorrect. C: Incorrect. D: Correct. E. Incorrect Molecules are only left out of equilibrium constants if they are pure solids or liquids. [ NO [ Cl [ NO Cl Mental Short Cut 1) since there is only one reactant and two products, focus on the reactants, ) recognize that the reactants will always be in the denominator, 3) stochiometry dictates that the denominator will be squared. 4) look for an answer with a square in the denominator, then confirm that it is the correct chemical species. 5) move on to the next question.

Question No. 4 of 10 Instruction: (1) Read the problem statement and answer choices carefully () Work the problems on paper as needed (3) Question 4: Which of the changes will shift the reaction to the right when disturbing equilibrium for N (g) + 3 H (g) NH 3 (g) + 9.94 kj? Question #04 I. Increasing temperature II. Decreasing temperature III. Increasing volume IV. Decreasing volume V. Removing NH 3 VI. Adding NH 3 VII. Removing N VIII. Adding N (A) I, IV, VI, VII (B) II, III, V, VIII (C) I, VI, VIII (D) II, IV, V, VIII (E) I, III, V, VIII A: Incorrect. Removing N is removing a reactant that would push the reaction to the left. B: Incorrect. Increasing volume lowers the pressure. The reaction will shift to the side with the greatest number of gas molecules to increase the pressure again. For this reaction, it would shift to the left. C: Incorrect. Increasing temperature for this reaction is an increase in a product that would push the reaction to the left. D: Correct. You chose all the options that would push the reaction to the right! E. Incorrect! Removing N is removing a reactant that would push the reaction to the left. I. Energy is a product. Increasing a product would push the reaction to the left. II. Energy is a product. Decreasing a product would push the reaction to the right III. Increasing volume pushes towards side with more moles of gas. The left has 4, the right has. It would push reaction towards left. IV. Decreasing volume pushes towards side with least moles of gas. It would push the reaction towards the right. V. Removing a product shifts the reaction towards the right VI. Adding a product shifts the reaction to the left VII. Removing a reactant shifts the reaction to the left VIII. Adding a reactant shifts the reaction to the right II, IV, V, VIII

Question No. 5 of 10 Instruction: (1) Read the problem statement and answer choices carefully () Work the problems on paper as needed (3) Question 5: For NOCl (g) NO (g) + Cl (g) with 1.6 10-5, if 1.0 M NOCl and 1.0 M Cl are added to a vessel, what are the equilibrium concentrations for each species? Question #05 (A) [NOCl = 1.0 M; [NO = 1.0 M; [Cl = 1.0 M (B) [NOCl = 1.0 M; [NO = 0.013 M; [Cl = 1.0 M (C) [NOCl = 1.0 M; [NO = 0.018 M; [Cl = 1.0 M (D) [NOCl = 1.0 M; [NO = 0.00016 M; [Cl = 1.0 M (E) [NOCl = 1.0 M; [NO = 0.000080 M; [Cl = 1.0 M A. Incorrect. Equilibrium does not necessarily mean that all concentrations are equal. B. Correct. You solved for equilibrium concentrations correctly! C. Incorrect. Use an ICE chart to solve for equilibrium concentrations. D. Incorrect. Use an ICE chart to solve for equilibrium concentrations. E. Incorrect. Use an ICE chart to solve for equilibrium concentrations. NOCl (g) NO (g) + Cl (g) 1.6 10-5 [NOCl initial = 1.0 M [Cl initial = 1.0 M [NO initial = 0 M Equilibrium concentrations of all 3 species Understanding the approximations used to solve this problem is VERY important. You will see them again. Believe it or not, the approximations make this problem easier to solve, not harder. They are worth learning. [ NO [ Cl [ NOCl [NOCl [NO [Cl Initial 1.0 M 0 M 1.0 M Change -x +x +x Equilibrium 1.0 x 0 + x 1.0 +x Since K is very tiny, approximations can be made for equilibrium concentrations Equilibrium 1.0 x 1.0 1.6 10 5 5 ( 1.6 10 ) [x [1.0 = [1.0 ( 1.0) ( 4) (1.0) = x x = 6.3 10-3 [NOCl = 1.0-0.0063 = 1.0 M [NO = 0 + 0.0063 = 0.013 M [Cl = 1.0 + 0.0063 = 1.0 M

Question No. 6 of 10 Instruction: (1) Read the problem statement and answer choices carefully () Work the problems on paper as needed (3) For the solubility equilibrium Ca(OH) (s) Ca + (aq) + OH -1 (aq), the addition of NaOH to the system will cause Question #06 (A) [OH - to increase as the mass of Ca(OH) in the system increases (B) [OH - to increase as the mass of Ca(OH) in the system remains the same (C) [OH - to decrease as the mass of Ca(OH) in the system increases (D) [OH - to decrease as the mass of Ca(OH) in the system decreases (E) [OH - to decrease as the mass of Ca(OH) in the system remains the same A. Correct. Adding a product will cause the reaction to shift to the left. B. Incorrect. Adding a product will cause the reaction to shift to the left. B. Incorrect. Adding a soluble hydroxide compound causes the hydroxide concentration to increase. D. Incorrect. Adding a product will cause the reaction to shift to the left. E. Incorrect. Adding a product will cause the reaction to shift to the left. Adding a product will cause the reaction to shift to the left. Adding a soluble hydroxide compound causes the hydroxide concentration to increase.

Question No. 7 of 10 Instruction: (1) Read the problem statement and answer choices carefully () Work the problems on paper as needed (3) Question 7: H + I HI Write the equilibrium constant expression for this all gas reaction? Question #07 (A) (B) (C) (D) (E) [ H [ I [ HI [ H [ I [ HI [ HI [ H [ I [ HI [ H [ I [ HI [ H[ I A: Incorrect. B: Incorrect. C: Correct. D: Incorrect. E. Incorrect! Ratio of products over reactants using balanced equation coefficients as powers [ HI [ H [ I

Question No. 8 of 10 Instruction: (1) Read the problem statement and answer choices carefully () Work the problems on paper as needed (3) Question 8: If the equilibrium constant K for the reaction A B + C is 5, what is the equilibrium constant for the reverse reaction at the same temperature? Question #08 (A) 6 (B) 5 (C) 1/5 (D) 1/6 (E) Cannot be determined A: Incorrect. When you flip a reaction, take the inverse of the equilibrium constant. B: Incorrect. When you flip a reaction, take the inverse of the equilibrium constant. C: Correct. When you flip a reaction, take the inverse of the equilibrium constant. D: Incorrect. When you flip a reaction, take the inverse of the equilibrium constant. E. Incorrect! When you flip a reaction, take the inverse of the equilibrium constant. When reversing the reaction, take the inverse of the equilibrium constant.

Question No. 9 of 10 Instruction: (1) Read the problem statement and answer choices carefully () Work the problems on paper as needed (3) Question 9. For the following gas reaction H + I HI What would be in the E row of the ICE chart below? Question #09 H I HI Initial 0.5 M 0.5 M 0 M Change Equilibrium (A) 0.5 M, 0.5 M, 0.5 M (B) x, -x, +x (C) 0.5 x, 0.5 x, x (D) +x, +x, -x (E) 0.5 + x, 0.5 + x, -x A. Incorrect. The reaction will shift to the right and have different final concentrations than the original concentrations because the product is initially 0 M. B. Incorrect. That is the C row of the ICE chart. C. Correct. You ve correctly determined the E row in the ICE chart. D. Incorrect. That information is similar to what would be in the C row except that the signs are opposite reactants will decrease and products will increase. E. Incorrect. The signs would be opposite as reactants would decrease and products would increase. H I HI Initial 0.5 M 0.5 M 0 M Change -x -x +x Equilibrium 0.5 M -x 0.5 -x x

Question No. 10 of 10 Instruction: (1) Read the problem statement and answer choices carefully () Work the problems on paper as needed (3) Question 10. Adding H to this gas system at equilibrium H + I HI Would cause which? Question #10 (A) Reaction would shift to the right (B) Reaction would shift to the left (C) Reaction would go both ways (D) No change (E) Cannot be determined A. Correct. B. Incorrect. C. Incorrect. D. Incorrect. E. Incorrect.