This quiz works best with JavaScript enabled. Home > Cbse > Class 11 > Science > Chemistry Part I > Class 11 Chemistry (Part I) Chapter 7 Equilibrium – Quiz 3 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 11 Chemistry (Part I) Chapter 7 Equilibrium Quiz 3 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. How does a catalyst affect a chemical equilibrium? A) It shifts the equilibrium position to the left. B) It increases the rate at which equilibrium is achieved without affecting the equilibrium position. C) It shifts the equilibrium position to the right. D) It decreases the rate at which equilibrium is achieved without affecting the equilibrium position. Show Answer Correct Answer: B) It increases the rate at which equilibrium is achieved without affecting the equilibrium position. 2. When the forward and reverse reactions are occurring at the same rate, the reaction is said to be at: A) Chemical equilibrium. B) Chemical peace. C) Chemical constant. D) Chemical reaction. Show Answer Correct Answer: A) Chemical equilibrium. 3. Such reactions which continue in both directions are called: A) Non-reactive reactions. B) Irreversible reactions. C) Dynamic reactions. D) Reversible reactions. Show Answer Correct Answer: D) Reversible reactions. 4. A push or a pull that acts on an object is: A) A force. B) Density. C) An ampere. D) A circuit. Show Answer Correct Answer: A) A force. 5. For an endothermic reaction, increasing the temperature A) Does not shift the equilibrium since K is a constant. B) Increases the rate of the reverse reaction to form more reactants. C) Increases the rate of the forward reaction to form more products. D) Increases the rate of the reverse reaction to form more products. Show Answer Correct Answer: C) Increases the rate of the forward reaction to form more products. 6. In a graph showing equilibrium of a gas reaction, what does a horizontal line indicate? A) Constant volume. B) Constant temperature. C) Constant concentration. D) Constant pressure. Show Answer Correct Answer: C) Constant concentration. 7. In a saturated solution of Zn(OH)$_{2}$ at 25$^{o}$C, the value of [OH$^{-}$] is 2.0 x 10$^{-6}$ M. What is the value of the solubility product constant, Ksp, for Zn(OH)$_{2}$ at 25$^{o}$C? A) 4.0 x 10$^{-18}$. B) 8.0 x 10$^{-18}$. C) 4.0 x 10$^{-12}$. D) 2.0 x 10$^{-6}$. E) 1.6 x 10$^{-17}$. Show Answer Correct Answer: A) 4.0 x 10$^{-18}$. 8. If a reaction is reversible and has reached equilibrium, what can be said about the amounts of reactants and products? A) Some reactant, some product. B) No reactant, all product. C) All reactant, no product. D) None of the above. Show Answer Correct Answer: A) Some reactant, some product. 9. Which of the following statements about chemical equilibrium is true? A) At equilibrium, the concentrations of reactants and products are equal. B) At equilibrium, the rate of the forward reaction equals the rate of the reverse reaction. C) At equilibrium, the reaction stops completely. D) At equilibrium, the concentration of products is always higher than that of reactants. Show Answer Correct Answer: B) At equilibrium, the rate of the forward reaction equals the rate of the reverse reaction. 10. What kind of force can be acting on an object in equilibrium? A) Unbalanced. B) Counter clockwise. C) Balanced. D) Clockwise. Show Answer Correct Answer: C) Balanced. 11. Which of the following changes in the supply of and the demand for a good will definitely result in a decrease in both the equilibrium price and quantity of the good? A) Supply-IncreaseDemand-Increase. B) Supply-IncreaseDemand-No change. C) Supply-No changeDemand-Decrease. D) Supply-DecreaseDemand-Increase. E) Supply-DecreaseDemand-Decrease. Show Answer Correct Answer: C) Supply-No changeDemand-Decrease. 12. What is the term used to describe the point where the forward and backward reactions in a reversible reaction occur at the same rate? A) Inhibition. B) Equilibrium. C) Activation energy. D) Catalysis. Show Answer Correct Answer: B) Equilibrium. 13. How does the addition of a catalyst affect the equilibrium constant of a reaction? A) It has no effect on the equilibrium constant. B) It decreases the equilibrium constant. C) It increases the equilibrium constant. D) It changes the equilibrium constant depending on the reaction. Show Answer Correct Answer: A) It has no effect on the equilibrium constant. 14. In a closed system at dynamic equilibrium, what happens if the concentration of a reactant is increased? A) The equilibrium remains unchanged. B) The reaction stops. C) The equilibrium shifts to the right, favoring the formation of products. D) The equilibrium shifts to the left, favoring the formation of reactants. Show Answer Correct Answer: C) The equilibrium shifts to the right, favoring the formation of products. 15. A 1000N man is playing on a seesaw with son who has a weight of 250N. If the child is sitting 4 meters away, how far will the man have to sit to balance the seesaw? A) 1m. B) 1.5m. C) 3m. D) 0.75m. Show Answer Correct Answer: A) 1m. 16. What happens to the level of national income, when aggregate supply exceeds aggregate demand? A) Increases. B) Decreases. C) Remains constant. D) None of the above. Show Answer Correct Answer: B) Decreases. 17. Can the value of the equilibrium constant (K) change with temperature? A) Only for endothermic reactions. B) No, the value of K remains constant regardless of temperature. C) Only for exothermic reactions. D) Yes, the value of K is temperature-dependent. Show Answer Correct Answer: D) Yes, the value of K is temperature-dependent. 18. Moment is the product of a force exerted on an object times the distance from applied force to the rotational axis. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 19. At equilibrium, the rate of the forward reaction is ..... the rate of the backward reaction A) Greater than. B) Equal to. C) Less than. D) None of the above. Show Answer Correct Answer: B) Equal to. 20. Which one of the following will change the value of an equilibrium constant? A) Adding other substances that do not react with any of the species involved in the equilibrium. B) Changing the volume of the reaction vessel. C) Changing temperature. D) Varying the initial concentrations of reactants. Show Answer Correct Answer: C) Changing temperature. 21. Below are the example of rigid body except: A) Beam. B) Cement. C) Slab. D) Column. Show Answer Correct Answer: B) Cement. 22. What is the K$_{eq}$ expression for this reaction? A) K$_{c }$= [NO$_{2}$]$^{2}$ / [NO]$^{2 }$[O$_{2}$]. B) K$_{c }$= [NO$_{2}$]$^{2}$ / [NO]$^{2}$ + [O$_{2}$]. C) K$_{c }$= [NO]$^{2 }$[O$_{2}$] / [NO$_{2}$]$^{2}$. D) K$_{c }$= [NO]$^{2 }$[O$_{2}$] [NO$_{2}$]$^{2}$. Show Answer Correct Answer: A) K$_{c }$= [NO$_{2}$]$^{2}$ / [NO]$^{2 }$[O$_{2}$]. 23. Jack has a weight of 300 N and sits 2.0 m from the pivot of see-saw. Jill has a weight of 450 N and sits 1.5 m from pivot. Who will move down? A) Jack. B) Jill. C) Both of them. D) None of them. Show Answer Correct Answer: B) Jill. 24. Suppose a doorknob is placed at the center of a door. Compared with a door whose knob is located at the edge, what amount of force must be applied to this door to produce the torque needed to open it? A) 1/2 as much. B) Four times as much. C) 1/4 as much. D) Twice as much. Show Answer Correct Answer: D) Twice as much. 25. Removing a reactant causes the reaction to shift in which direction (reactants + reagents $\rightarrow$ products) A) Left. B) Right. C) It doesnt. D) None of the above. Show Answer Correct Answer: A) Left. 26. Which factors increase the rate of a reaction. A) Increasing temperature. B) Increasing concentration. C) Increasing surface area. D) All of these. Show Answer Correct Answer: D) All of these. 27. In a laboratory experiment, a student adds a small amount of sodium chloride to a saturated solution of sodium chloride. What is the expected observation? A) The solution remains unchanged. B) Sodium chloride precipitates out of the solution. C) The solubility of sodium chloride increases. D) The solution becomes unsaturated. Show Answer Correct Answer: B) Sodium chloride precipitates out of the solution. 28. What factor can be increased to provide more collisions for gases only? A) Pressure. B) Temperature. C) Surface area. D) Adding a catalyst. Show Answer Correct Answer: A) Pressure. 29. In a population of bears, the frequency of q is 0.44. What is the frequency of p? A) 0.1936. B) 0.22. C) 0.44. D) 0.56. Show Answer Correct Answer: D) 0.56. 30. A thin 1 m long rod has a 200 g object attached to the left end and a 300 g object attached to the right end. If the pivot point is in the middle of the rod, the object ..... A) Will be in static rotational equilibrium. B) Will have a positive angular position. C) Will have a negative angular position. D) Is balanced. Show Answer Correct Answer: C) Will have a negative angular position. 31. What happens to the position of equilibrium when the concentration of a reactant is increased? A) The equilibrium remains unchanged. B) The equilibrium shifts to the right. C) The equilibrium shifts to the left. D) The reaction stops. Show Answer Correct Answer: B) The equilibrium shifts to the right. 32. In a chemical equilibrium, what happens to the concentrations of reactants and products when a catalyst is added? A) The concentrations of reactants and products remain unchanged. B) The concentration of reactants increases. C) The concentration of products increases. D) Both reactants and products are consumed. Show Answer Correct Answer: A) The concentrations of reactants and products remain unchanged. 33. In the reaction @@ext{N} ..... 2(g) + 3ext{H} ..... 2(g) ightleftharpoons 2ext{NH} ..... 3(g)@@, what happens to the equilibrium position if the pressure is increased? A) Shifts to the right, favoring the formation of $\text{NH}_3$. B) Remains unchanged. C) The reaction stops. D) Shifts to the left, favoring the formation of $\text{N}_2$ $\text{H}_2$. Show Answer Correct Answer: A) Shifts to the right, favoring the formation of $\text{NH}_3$. 34. Higher indifference curve represents A) No satisfaction. B) Higher level of satisfaction. C) Medium level of satisfaction. D) Lower level of satisfaction. Show Answer Correct Answer: B) Higher level of satisfaction. 35. For equilibrium to occur ..... A) The reactants must be in an open system. B) The reactants must be in a closed system. C) The reactants can be in either a closed or open system. D) None of the above. Show Answer Correct Answer: B) The reactants must be in a closed system. 36. Which of the following does not affect the position of equilibrium? A) Concentration. B) Temperature. C) Particle Size. D) Pressure. Show Answer Correct Answer: C) Particle Size. 37. Neutral equilibrium A) A kind of equilibrium so that with a small or insignificant change, it still remains in a state of equilibrium. B) A kind of equilibrium so that when the object is slightly changed, it go further from its original position. C) A kind of equilibrium so that with a small change, forces emerge which help return the object back into a state of equilibrium. D) None. Show Answer Correct Answer: A) A kind of equilibrium so that with a small or insignificant change, it still remains in a state of equilibrium. 38. What happens to the concentrations of the reactants and products at equilibrium? A) They decrease. B) They remain constant. C) They become zero. D) They increase. Show Answer Correct Answer: B) They remain constant. 39. What is true for catalyst in a chemical reaction? A) It impacts the equilibrium constant. B) It disturbs the equilibrium composition. C) It helps to attain the equilibrium faster. D) None of the above. Show Answer Correct Answer: C) It helps to attain the equilibrium faster. 40. Equilibria in which all substances are in the same phases are called A) Dynamic equilibrium. B) Homogeneous equilibria. C) Heterogeneous equilibria. D) Equilibrium constant. Show Answer Correct Answer: B) Homogeneous equilibria. 41. A chemical equilibrium exists when: A) Reactants are completely changed to products. B) There are equal amounts of reactants and products. C) The rate at which reactants form products becomes zero. D) The rate at which reactants form products is the same as the rate at which products form reactants. Show Answer Correct Answer: D) The rate at which reactants form products is the same as the rate at which products form reactants. 42. PKa values of two acids A and B are 4 and 5. The strengths of these two acids are related as A) The strengths of the two acids can not be compared. B) Acid B is 10 times stronger than acid A. C) Acid A is 10 times stronger than acids B. D) Strength of acid A:strengtha of acid B = 4:5. Show Answer Correct Answer: C) Acid A is 10 times stronger than acids B. 43. The partial pressures in a system always add up to: A) The total pressure. B) 1. C) 100. D) 0. Show Answer Correct Answer: A) The total pressure. 44. Equilibrium is a ..... process A) Fictitious. B) Probabilistic. C) Static. D) Dynamic. Show Answer Correct Answer: D) Dynamic. 45. TRUE or FALSE: "At equilibrium, the RATES of the forward and reverse reactions are EQUAL" A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 46. Which is the correct equilibrium constant expression for the following reaction? Fe$_{2}$O$_{3(s)}$ + 3H$_{2(g)}$ $\rightarrow$ 2Fe$_{(s)}$ + 3H$_{2}$O$_{(g)}$ A) K = [H$_{2}$] / [H$_{2}$O]. B) K = [Fe$_{2}$O$_{3}$] [H$_{2}$]$^{3}$ / [Fe]$^{2}$[H$_{2}$O]$^{3 }$. C) K = [H$_{2}$O]3 / [H$_{2}$]$^{3}$. D) K= [Fe] [H$_{2}$O] / [Fe$_{2}$O$_{3}$] [H$_{2}$]. E) K = [Fe]$^{2}$[H$_{2}$O]$^{3}$ / [Fe$_{2 }$O$_{3}$] [H$_{2}$]$^{3}$. Show Answer Correct Answer: C) K = [H$_{2}$O]3 / [H$_{2}$]$^{3}$. 47. A population's recessive allele frequency 25%. What is the percentage of the Heterozygous genotype? A) .5625. B) .25. C) .5. D) .3750. E) .0625. Show Answer Correct Answer: D) .3750. 48. Which of the following statements is true about the equilibrium constant (K) for a chemical reaction? A) K is always greater than 1 for all reactions. B) K is independent of temperature. C) K is a measure of the extent of a reaction at equilibrium. D) K is always less than 1 for all reactions. Show Answer Correct Answer: C) K is a measure of the extent of a reaction at equilibrium. 49. Which description below best describes what is happening when a reversible reaction has reached equilibrium? A) There are no more reactants left and only products are present. B) No reactants are combining anymore and no products are being produced. C) Reactants are still combining to form products but the products are forming reactants at the same rate. D) No reactants are combining anymore and products are now breaking apart to make more reactants. Show Answer Correct Answer: C) Reactants are still combining to form products but the products are forming reactants at the same rate. 50. A uniform beam is 10 meters long and weighs 200N. It is supported at its center. A 300N weight is placed 2 meters from one end. Where should a 100N weight be placed to balance the beam? A) 1 meter from the opposite end. B) 7 meters from the opposite end. C) 5 meters from the opposite end. D) 3 meters from the opposite end. Show Answer Correct Answer: D) 3 meters from the opposite end. 51. A resultant is ..... A) The sum of two or more vectors. B) All the addition you did. C) Combination of forces together. D) What happens when two people get on a scale together. Show Answer Correct Answer: A) The sum of two or more vectors. 52. For the reaction ..... H$_{2 (g) }$ + Cl$_{2 (g) }$<=> 2HCl $_{(g) }$ + heatIf the pressure in the system is increased, the equilibrium position will ..... A) Shift to the left. B) Shift to the right. C) Not shift position at all as 2 mol gas <=> 2 mol gas. D) None of the above. Show Answer Correct Answer: C) Not shift position at all as 2 mol gas <=> 2 mol gas. 53. In the reaction @@ext{A} + ext{B} ightleftharpoons ext{C} + ext{D}@@, what happens to the equilibrium position if the concentration of A is increased? A) The equilibrium shifts to the left. B) The equilibrium remains unchanged. C) The reaction stops. D) The equilibrium shifts to the right. Show Answer Correct Answer: D) The equilibrium shifts to the right. 54. What is the common ion effect in solubility equilibrium? A) The increase in solubility of a salt when a common ion is added. B) The increase in temperature of a solution when a common ion is added. C) The change in color of a solution when a common ion is added. D) The decrease in solubility of a salt when a common ion is added. Show Answer Correct Answer: D) The decrease in solubility of a salt when a common ion is added. 55. At equilibrium, concentrations of reactants and products are A) Equal. B) Constant. C) All the above. D) None of the above. Show Answer Correct Answer: B) Constant. 56. When Marginal Utility is zero what happens to Total Utility? A) Became Zero. B) Became Maximum. C) Became Minimum. D) None of these. Show Answer Correct Answer: B) Became Maximum. 57. The value of Ksp for PbCl$_{2}$ is 1.6 x 10$^{-5}$. What is the lowest concentration of Cl$^{-}$ (aq) that would be needed to begin precipitation of PbCl$_{2}$ (s) in 0.010 M Pb(NO$_{3}$)$_{2}$? A) 1.6 x 10$^{-3}$ M. B) 1.6 x 10$^{-7}$ M. C) 4.0 x 10$^{-4}$ M. D) 4.0 x 10$^{-2}$ M. E) 2.6 x 10$^{-7}$ M. Show Answer Correct Answer: D) 4.0 x 10$^{-2}$ M. 58. Which of the following is NOT true at equilibrium? A) The forward and reverse reactions proceed at the same rate. B) The concentrations of reactants and products do not change. C) The concentration of the reactants is equal to the concentration of the products. D) The forward and reverse reactions continue to occur. Show Answer Correct Answer: C) The concentration of the reactants is equal to the concentration of the products. 59. Which of the following is another name for excess demand? A) Surplus. B) Equilibrium. C) Shortage. D) Disequilibrium. Show Answer Correct Answer: C) Shortage. 60. Any point inside PPC represents:- A) Underutilized resources. B) Fully utilized resources. C) Unattainable of resources. D) All of the above. Show Answer Correct Answer: A) Underutilized resources. ← PreviousNext →Related QuizzesScience QuizzesClass 11 QuizzesClass 11 Chemistry (Part I) Chapter 7 Equilibrium Quiz 1Class 11 Chemistry (Part I) Chapter 7 Equilibrium Quiz 2Class 11 Chemistry (Part I) Chapter 7 Equilibrium Quiz 4Class 11 Chemistry (Part I) Chapter 7 Equilibrium Quiz 5Class 11 Chemistry (Part I) Chapter 7 Equilibrium Quiz 6Class 11 Chemistry (Part I) Chapter 7 Equilibrium Quiz 7Class 11 Chemistry (Part I) Chapter 7 Equilibrium Quiz 8Class 11 Chemistry (Part I) Chapter 7 Equilibrium Quiz 9 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books