Guldberg ratio

Quldberg Ratio The normal boiling point divided by the critical temperature is the Guldberg ratio  

Relationships between Tb and Nc or M in homologous series are nonlinear. The difference in Tb between successive members of n-alkanes is not constant. It falls off continuously, demonstrated by plotting Tb against Nc (C1-C40) [5]. The following equation has been reported for n-alkanes (C6-C18) [6,7]  

Tb values of perfluorinated n-alkanes have been fitted into the following model (C,-C16) [8]  

A compilation of structure-7 relationships for homologous series has been given by Horvath [9]. This author also reviews various other structure-relationships. Most of the available methods are restricted to classes of certain hydrocarbons or monofunctional derivatives thereof. In the following, models have been selected in which different molecular descriptors are employed to estimate Tb. 

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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. 

In 1879 Guldberg and Waage substituted the above formulation for the basic law of chemical reactions by its modem version in terms of the concept of mobile equilibrium. For the interaction between the initial substances A, B, C, taken in the stoichiometric ratio of a to to y, i.e. aA + / B + yC, the reaction rate, W, was expressed as... 

Ramsay and Young also found that for a given pressure the ratio of the absolute temperature to the absolute critical temperature is approximately consent. This is an extension of Guldberg s rule ( 7.VII C). Adams found that the b.p. abs. at p atm. is related to that at 1 atm. by the formula ... 

In 1864, the Norwegian chemists Cato Maximilian Guldberg and Peter Waage proposed the law of chemical equilibrium, which states that at a given temperature, a chemical system may reach a state in which a particular ratio of reactant and product concentrations has a constant value. For example, the general equation for a reaction at equilibrium can be written as follows. 

In their experiments, Guldberg and Waage found the ratio... 

The Guldberg-Waage curve at ioo was also determined, and it was found that the ratio KgCOg K2SO4 is also not constant, although the variations are not so great as at 25 . 

Guldberg and Waage proposed the definition of the equilibrium constant as a certain ratio of concentrations. What relationship allows us to use a particular ratio of partial pressures (for a gaseous reaction) to express an equilibrium constant Explain. 

The law of chemical equilibrium as proposed by Guldberg and Waage is based on experimentai observations. Experiments on many reactions showed that the equiiibrium condition could always be described by this special ratio, called the equilibrium expression. 

Though the concentrations of A, B, C, and D at equilibrium would shift as one or more of these components were added to or taken from the mixture, Guldberg and Waage found they could cling to one unchanging factor. The ratio of the product of the concentrations of the substances on one side of the double arrow to the product of the concentrations on the other side of the double arrow, at equilibrium, remains constant. 

Equation 10.1 is an example of the law of mass action, which holds that for a reversible reaction at equilibrium and at a constant temperature, a certain ratio of reactant and product concentrations has a constant value K (called the equilibrium constant). This law was first formulated by two Norwegian chemists, Cato Guldberg and Peter Waage, in 1864. 

It shall also be remembered that the first derivation of the law of mass action by Guldberg and Waage was based on a kinetic approach. They obtained the equihbrium constant, a thermodynamic quantity, as the ratio of the rate constants, i.e. kinetic quantities, for the forward and back reactions. 

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