\nThe rate at which a substance reacts is proportional to its active mass, and hence the rate of a reaction is proportional to the product of the active masses of the reactants, each raised to the power equal to its stoichiometric coefficient as represented by the balanced chemical equation. \n The term 'Active Mass' used in the above definition means molar concentration, i.e., number of moles dissolved per litre of the solution.
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Example:
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(i) , on applying the law of mass action,
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The rate of a forward reaction, Where, represent the active masses of hydrogen and iodine and is a constant of proportionality and is called velocity constant for the forward reaction.
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Consider the more general reversible reaction, ,
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On applying the 'Law of Mass Action', the rate of the forward reaction, , and the rate of the backward reaction. At equilibrium, Rate of the forward reactionRate of the backward reaction. Therefore, ,
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where is an equilibrium constant.
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The product of the molar concentrations of the products, each raised to the power equal to its stoichiometric coefficient divided by the product of the molar concentrations of the reactants, each raised to the power equal to its stoichiometric coefficient is constant at constant temperature and is called equilibrium constant, and is denoted by .
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\n"},"comment":{"@type":"Comment","text":"This law explains the dependence of the rate of the reaction on the concentration of the reactants."},"encodingFormat":"text/markdown","learningResourceType":"Practice problem","suggestedAnswer":[],"text":"Define and explain law of mass action. What is an equilibrium constant?"},"name":"Quiz on Equilibria","typicalAgeRange":"10-17","url":"https://www.embibe.com/questions/Define-and-explain-law-of-mass-action.-What-is-an-equilibrium-constant%3F/EM7747019"}
Odisha Board Solutions for Chapter: Equilibria, Exercise 1: QUESTIONS
Author:Odisha Board
Odisha Board Chemistry Solutions for Exercise - Odisha Board Solutions for Chapter: Equilibria, Exercise 1: QUESTIONS
Attempt the practice questions on Chapter 9: Equilibria, Exercise 1: QUESTIONS with hints and solutions to strengthen your understanding. Bureau's Higher Secondary Chemistry Volume-1 solutions are prepared by Experienced Embibe Experts.
Questions from Odisha Board Solutions for Chapter: Equilibria, Exercise 1: QUESTIONS with Hints & Solutions