Equilibrium law of chemical

These observations and many others like them lead to the generalization known as the Law of Chemical Equilibrium. For a reaction... 

The Law of Chemical Equilibrium Derived from Rates of Opposing Reactions... 

Chemists picture equilibrium as a dynamic balance between opposing reactions. An understanding of the Law of Chemical Equilibrium can be built upon this basis. 

We have gone further and discovered that the equilibrium conditions imply a constant relationship among the concentrations of reactants and products. This relationship is called the Law of Chemical Equilibrium. Using this law, we can express the conditions at equilibrium in terms of a number K, called the equilibrium constant. 

Guldberg and Waage (1867) clearly stated the Law of Mass Action (sometimes termed the Law of Chemical Equilibrium) in the form The velocity of a chemical reaction is proportional to the product of the active masses of the reacting substances . Active mass was interpreted as concentration and expressed in moles per litre. By applying the law to homogeneous systems, that is to systems in which all the reactants are present in one phase, for example in solution, we can arrive at a mathematical expression for the condition of equilibrium in a reversible reaction. 

The fundamental law of chemical equilibrium is the law of mass action, formulated in 1864 by Cato Maximilian Guldberg and Peter Waage. It has since been redefined several times. Consider the equilibrium between the four chemical species A, B, C and D ... 

Volume 3 explains the systems of molecular and atomic weight, valences, the atomic theory, the system of classification of the elements, and the laws of chemical equilibrium. Here we find Lespieau s view that the goal of chemistry is the formule developee, not the formule brute, and that the atomic hypothesis gives us a striking interpretation and creates a language that is now adopted by all chemists, even those who reject the hypothesis of an indivisible primordial particle.30... 

In 1864, two Norwegian chemists, Cato Guldberg and Peter Waage, summarized their experiments on chemical equilibrium in the law of chemical equilibrium At equilibrium, there is a constant ratio between the concentrations of the products and reactants in any change. 

Figure 7.7 shows how the law of chemical equilibrium applies to one chemical system. Chemists have studied this system extensively. It involves the reversible reaction between two gases dinitrogen tetroxide, which is colourless, and nitrogen dioxide, which is dark brown. 

The law of chemical equilibrium is sometimes known as the law of mass action. Before the term "concentration" was used, the concept of amount per unit volume was called "active mass."... 

CHEMICAL EQUILIBRIUM. The fundamental law of chemical equilibrium was enunciated by Le Chalclier (I884i. and may be stated as follows If any stress or force is brought to bear upon a system in equilibrium, the equilibrium is displaced in a direction which lends to diminish the intensity ol the stress or force. This is equivalent to the principle of least aclion. Its great value to the chemist is that it enahles him to predict the effect upon systems in equilibrium ol changes in temperature, pressure, and concentration. 

In (19-6), n has been made dimensionless. For a half-reaction, n is the number of electrons in the half-equation for the whole-cell reaction, n is the number of electrons in one of the multiplied half-equations before canceling the electrons. The Nernst equation is closely related to the laws of chemical equilibrium. Le Chatelier s principle applies to the potential of a cell in the same sense as it applies to the yield of an equilibrium process. Since Q is a fraction that has product concentrations in the numerator (top) and reactant concentrations in the denominator (bottom), an increased concentration of the product reduces the potential and an increased concentration of reactant raises the potential. 

The Law of Chemical Equilibrium is based on the constancy of the equilibrium constant. This means that if one disturbs the equilibrium, for example by adding more reactant molecules, there will be an increase in the number of product molecules in order to maintain the producl/reactant ratio unchanged and thus preserving the numerical value of the equilibrium constant. The Le Chatelier Principle expresses this as follows If an external stress is applied to a system in equilibrium, the system reacts in such a way as to partially relieve the stress. In our present experiment, we demonstrate the Le Chatelier Principle in two manners (a) disturbing the equilibrium by changing the concentration of a product or reactant (b) changing the temperature. 

Also the so called degree of dissociation, determined from the colligative properties, does not agree with the result obtained from the measurement of the electrical conductance. Finally the law of chemical equilibrium, applicable to the dissociation of weak electrolytes, cannot be applied to the strong ones. 

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