Macmillan Learning Recall that when a reaction is at equilibrium, the forward and reverse reactions occur at the same rate. To illustrate this idea, consider the reaction of A (small, red spheres) and B (large, blue spheres) to form AB. A+B AB The image shows a snapshot of the reaction at equilibrium. Although the image only shows a snapshot of the reaction at equilibrium, the reaction never stops. Even after several minutes, there is some A and B left unreacted, and the forward and reverse reactions continue to occur. Also, the amounts of each species (i.e., their concentrations) stay the same. Assume each atom or molecule represents a 1 M concentration of that substance. What is the value of the equilibrium constant for this reaction? K=

Macmillan Learning Recall that when a reaction is at equilibrium, the forward and reverse reactions occur at the same rate. To illustrate this idea, consider the reaction of A (small, red spheres) and B (large, blue spheres) to form AB. A+B AB The image shows a snapshot of the reaction at equilibrium. Although the image only shows a snapshot of the reaction at equilibrium, the reaction never stops. Even after several minutes, there is some A and B left unreacted, and the forward and reverse reactions continue to occur. Also, the amounts of each species (i.e., their concentrations) stay the same. Assume each atom or molecule represents a 1 M concentration of that substance. What is the value of the equilibrium constant for this reaction? K=

Introductory Chemistry: A Foundation

9th Edition

ISBN:9781337399425

Author:Steven S. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Donald J. DeCoste

Chapter17: Equilibrium

Section: Chapter Questions

Problem 1ALQ: Consider an equilibrium mixture of four chemicals (A. B. C. and D. all gases) reacting in a closed...

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When writing a chemical equation for a reaction that comes to equilibrium. how do we indicate symbolically that the reaction is reversible?
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. Explain what it means that a reaction has reached a state of chemical equilibrium. Explain why equilibrium is a dynamic state: Does a reaction really “stop” when the system reaches a state of equilibrium? Explain why, once a chemical system has reached equilibrium, the concentrations of all reactants remain constant with time. Why does this constancy of concentration not contradict our picture of equilibrium as being dynamic? What happens to the rates of the forward and reverse reactions as a system proceeds to equilibrium from a starting point where only reactants are present?
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The experiment in Exercise 12.33 was redesigned so that the reaction started with 0.15 mol each of N2 and O2 being injected into a 1.0-L container at 2500 K. The equilibrium constant at 2500 K is 3.6 X 10“’. What was the composition of the reaction mixture after equilibrium was attained? The following reaction establishes equilibrium at 2000 K: N2(g) + O2(g) *2 2 NO K = 4.1 X IO-4 If the reaction began with 0.100 mol L-1 of N2 and 0.100 mol L-’ ofO2, what were the equilibrium concentrations of all species?
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Consider the isomerization of butane with an equilibrium constant of K = 2.5. (See Study Question 13.) The system is originally at equilibrium with [butane] = 1.0 M and [isobutane] = 2.5 M. (a) If 0.50 mol/L of isobutane is suddenly added and the system shifts to a new equilibrium position, what is the equilibrium concentration of each gas? (b) If 0.50 mol/L of butane is added to the original equilibrium mixture and the system shifts to a new equilibrium position, what is the equilibrium concentration of each gas?
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