Textbook Question
Write the expressions for 𝐾𝑐 for the following reactions. In each case indicate whether the reaction is homogeneous or heterogeneous.
(b) Ti(𝑠) + 2Cl2(𝑔) ⇌ TiCl4(𝑙)
Ch.15 - Chemical Equilibrium
Brown15th EditionChemistry: The Central ScienceISBN: 9780137542970
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Table of contents
- Ch.1 - Introduction: Matter, Energy, and Measurement146
- Ch.2 - Atoms, Molecules, and Ions200
- Ch.3 - Chemical Reactions and Reaction Stoichiometry176
- Ch.4 - Reactions in Aqueous Solution155
- Ch.5 - Thermochemistry126
- Ch.6 - Electronic Structure of Atoms131
- Ch.7 - Periodic Properties of the Elements126
- Ch.8 - Basic Concepts of Chemical Bonding123
- Ch.9 - Molecular Geometry and Bonding Theories143
- Ch.10 - Gases147
- Ch.11 - Liquids and Intermolecular Forces91
- Ch.12 - Solids and Modern Materials122
- Ch.13 - Properties of Solutions126
- Ch.14 - Chemical Kinetics174
- Ch.15 - Chemical Equilibrium101
- Ch.16 - Acid-Base Equilibria139
- Ch.17 - Additional Aspects of Aqueous Equilibria146
- Ch.18 - Chemistry of the Environment72
- Ch.19 - Chemical Thermodynamics129
- Ch.20 - Electrochemistry142
- Ch.21 - Nuclear Chemistry101
- Ch.22 - Chemistry of the Nonmetals68
- Ch.23 - Transition Metals and Coordination Chemistry66
- Ch.24 - The Chemistry of Life: Organic and Biological Chemistry10
Brown15th EditionChemistry: The Central ScienceISBN: 9780137542970Not the one you use?Change textbook
Chapter 15, Problem 17
When the following reactions come to equilibrium, does the equilibrium mixture contain mostly reactants or mostly products? (a) N2(g) + O2(g) ⇌ 2 NO(g), Kc = 1.5 × 10^-10 (b) 2 SO2(g) + O2(g) ⇌ 2 SO3(g), Kp = 2.5 × 10^9
Verified step by step guidance1
Step 1: Understand the concept of equilibrium constant (K). The equilibrium constant (K) is a measure of the extent of a reaction at equilibrium. A large K value (K >> 1) indicates that the reaction favors the formation of products, while a small K value (K << 1) indicates that the reaction favors the formation of reactants.
Step 2: Analyze reaction (a) N2(g) + O2(g) ⇌ 2 NO(g) with Kc = 1.5 × 10^-10. Since Kc is much less than 1, this suggests that at equilibrium, the concentration of reactants (N2 and O2) is much greater than the concentration of products (NO).
Step 3: Conclude for reaction (a) that the equilibrium mixture contains mostly reactants because the equilibrium constant is very small, indicating the reaction does not proceed far towards products.
Step 4: Analyze reaction (b) 2 SO2(g) + O2(g) ⇌ 2 SO3(g) with Kp = 2.5 × 10^9. Since Kp is much greater than 1, this suggests that at equilibrium, the concentration of products (SO3) is much greater than the concentration of reactants (SO2 and O2).
Step 5: Conclude for reaction (b) that the equilibrium mixture contains mostly products because the equilibrium constant is very large, indicating the reaction proceeds significantly towards products.
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Chemical Equilibrium
Chemical equilibrium occurs when the rates of the forward and reverse reactions are equal, resulting in constant concentrations of reactants and products. At this point, the system is dynamic, meaning that reactions continue to occur, but there is no net change in the concentrations of the substances involved.
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04:21
Chemical Equilibrium Concepts
Equilibrium Constant (K)
The equilibrium constant (K) quantifies the ratio of the concentrations of products to reactants at equilibrium for a given reaction at a specific temperature. A large K value (much greater than 1) indicates that products are favored at equilibrium, while a small K value (much less than 1) suggests that reactants are favored.
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01:14Equilibrium Constant K
Le Chatelier's Principle
Le Chatelier's Principle states that if a system at equilibrium is disturbed by changes in concentration, temperature, or pressure, the system will adjust to counteract the disturbance and restore a new equilibrium. This principle helps predict how changes will affect the position of equilibrium in a reaction.
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07:32Le Chatelier's Principle
Related Practice
Textbook Question
Write the expressions for Kc for the following reactions. In each case indicate whether the reaction is homogeneous or heterogeneous.
(a) 2 O3(g) ⇌ 3 O2(g)
(c) 2 C2H4(g) + 2 H2O(g) ⇌ 2 C2H6(g) + O2(g)
(d) C(s) + 2 H2(g) ⇌ CH4(g)
(e) 4 HCl(aq) + O2(g) ⇌ 2 H2O(l) + 2 Cl2(g)
(f) 2 C8H18(l) + 25 O2(g) ⇌ 16 CO2(g) + 18 H2O(g)
(g) 2 C8H18(l) + 25 O2(g) ⇌ 16 CO2(g) + 18 H2O(l)
Textbook Question
Write the expression for Kc for the following reactions. In each case indicate whether the reaction is homogeneous or heterogeneous.
(a) 3 NO(g) ⇌ N2O(g) + NO2(g)
(b) CH4(g) + 2 H2S(g) ⇌ CS2(g) + 4 H2(g)
(c) Ni(CO)4(g) ⇌ Ni(s) + 4 CO(g)
(d) HF(aq) ⇌ H+(aq) + F-(aq)
(e) 2Ag(s) + Zn2+(aq) ⇌ 2 Ag+(aq) + Zn(s)
(f) H2O(l) ⇌ H+(aq) + OH-(aq)
(g) 2 H2O(l) ⇌ 2 H+(aq) + 2 OH-(aq)
Textbook Question
Which of the following statements are true and which are false? (c) As the value of the equilibrium constant increases, the speed at which a reaction reaches equilibrium must increase.
Textbook Question
Which of the following reactions lies to the right, favoring the formation of products, and which lies to the left, favoring the formation of reactants?
(a) 2 NO(g) + O2(g) ⇌ 2 NO2(g) Kp = 5.0 × 1012
(b) 2 HBr(g) ⇌ H2(g) + Br2(g) Kc = 5.8×10−18