Anthocyanins(represented as A (aq)) are responsible for the red colour of wine. Anthocyanins can react with water as follows 2 H:O(1) + A*(aq) – H3O*(aq) + AOH(aq) The equilibrium concentration of the H30* (aq) is 8.5 x 10 mol/L. If the initial concentration of anthocyanins, prior to equilibrium, was 1.62 x 103 mol/L, the K, for the anthocyanins is

Anthocyanins(represented as A (aq)) are responsible for the red colour of wine. Anthocyanins can react with water as follows 2 H:O(1) + A(aq) – H3O(aq) + AOH(aq) The equilibrium concentration of the H30* (aq) is 8.5 x 10 mol/L. If the initial concentration of anthocyanins, prior to equilibrium, was 1.62 x 103 mol/L, the K, for the anthocyanins is

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter12: Chemical Equilibrium

Section: Chapter Questions

Problem 7QRT

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Because calcium carbonate is a sink for CO32- in a lake, the student in Exercise 12.39 decides to go a step further and examine the equilibrium between carbonate ion and CaCOj. The reaction is Ca2+(aq) + COj2_(aq) ** CaCO,(s) The equilibrium constant for this reaction is 2.1 X 10*. If the initial calcium ion concentration is 0.02 AI and the carbonate concentration is 0.03 AI, what are the equilibrium concentrations of the ions? A student is simulating the carbonic acid—hydrogen carbonate equilibrium in a lake: H2COj(aq) H+(aq) + HCO}‘(aq) K = 4.4 X 10"7 She starts with 0.1000 AI carbonic acid. What are the concentrations of all species at equilibrium?
In a particular experiment, the equilibrium constant measured for the reaction, Cl2(g)+NO2(g)Cl2NO2(g), is 2.8. Based on this measurement, calculate AG° for this reaction. Calculate AG° using data from Appendix E at the back of the book and discuss the agreement between your two calculations.
The reaction, 3 H2(g) + N2(g) (g), has the fol lowing equilibrium constants at the temperatures given: atT=25°C,K= 2.8 X 104 at T = 500°C, A = 2.4 X IO"7 At which temperature are reactants favored? At which temperature are products favored? YVhat can you say about the reaction if the equilibrium constant is 1.2 at 127°C?
Consider the system 4 NH3(g) + 3 O2(g) ⇌ 2 N2(g) + 6 H20(ℓ) ΔrH° = −1530.4 kJ/mol How will the amount of ammonia at equilibrium be affected by removing O2(g) without changing the total gas volume? adding N2(g) without changing the total gas volume? adding water without changing the total gas volume? expanding the container? increasing the temperature? Which of these changes (i to v) increases the value of K? Which decreases it?
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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The following data were collected for a system at equilibrium at 140°C. Calculate the equilibrium constant for the reaction, 3 H2(g) + N2(g) 5=^ 2 NHt(g) at this temperature. [H2] = 0.10 mol L_1, [NJ = 1.1 mol L"1, [NHJ = 3.6 X 10"-mol L'1
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For the reactionH2(g)+I2(g)2HI(g), consider two possibilities: (a) you mix 0.5 mole of each reactant. allow the system to come to equilibrium, and then add another mole of H2 and allow the system to reach equilibrium again. or (b) you mix 1.5 moles of H2 and 0.5 mole of I2 and allow the system to reach equilibrium. Will the final equilibrium mixture be different for the two procedures? Explain.