Chemical composition constant proportions

Charles s law The volume of a given sample of gas at constant pressure is directly proportional to its absolute temperature V T. chelate A complex containing at least one polydentate ligand that forms a ring of atoms including the central metal atom. Example [Co(en)3]3+. chemical analysis The determination of the chemical composition of a sample. See also qualitative, quantitative. 

The growth rate, characterized by the change of the radius with time, is proportional to the driving force for the phase separation, given by the differences between 2 > the chemical composition of the second phase in the continuous phase at any time, and, its equihbrium composition given by the binodal line. The proportionahty factor, given by the quotient of the diffusion constant, D, and the radius, r, is called mass transfer coefficient. Furthermore the difference between the initial amount of solvent, (])o, and c]) must be considered. The growth rate is mathematically expressed by [101]... 

The first strides after recognition of mass conservation led to the formulation of several phenomenological laws of chemical composition, such as the laws of constant proportions, multiple proportions and eguivalent proportions, found to be obeyed during interaction between chemical substances. These laws served to catalogue and systematize a large body of empirical... 

The consequence of the inevitable adaptation of a catalyst to the reac tion medium was formulated by G. Boreskov in 1947 as a particular rule In stationary conditions, the specific catalytic activity, SCA, of a heteroge neous catalyst (i.e., the rate of the catalytic reaction per unit of exposed surface of the catalyticaUy active phase) is approximately constant at a given temperature and the reaction medium composition, thus SCA being dependent only on the chemical composition of the active catalyst phase. At present, turnover frequency (TOF) of the active center is normally used instead of SCA to characterize the activity of the center, TOF being in direct proportion to SCA. The Boreskov rule is evidently valid for the TOF value, too. 

The structural formula reveals that this polymer contains two different types of carboxyl group which have different dissociation constants. While the first dissociation step is characterized by a pK value of 3.4, the pK value of the second step is about 7.4. Both pK values were determined via titration of the prepolymer with sodium hydroxide solution. The exchange capacity of the finished stationary phase is directly proportional to its polymer content. It may be calculated in advance, since, owing to the chemical composition, the concentration of the exchange groups in the prepolymer is known. 

The basis of chemistry as it grew up in the nineteenth century is Dalton s atomic theory. In this the intuitive idea of ultimate particles is applied to explain definite quantitative laws of chemical composition, those, namely, of constant, multiple, and reciprocal proportions. These rules could only have emerged after a long empirical study... 

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