A Quote by Dmitri Mendeleev
Elements which are similar as regards their chemical properties have atomic weights which are either of nearly the same value (eg. Pt, Ir, Os) or which increase regularly (eg. K, Ru, Cs).
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Probably our atomic weights merely represent a mean value around which the actual atomic weights of the atoms vary within certain narrow limits... when we say, the atomic weight of, for instance, calcium is 40, we really express the fact that, while the majority of calcium atoms have an actual atomic weight of 40, there are not but a few which are represented by 39 or 41, a less number by 38 or 42, and so on.
[This] may prove to be the beginning of some embracing generalization, which will throw light, not only on radioactive processes, but on elements in general and the Periodic Law.... Chemical homogeneity is no longer a guarantee that any supposed element is not a mixture of several of different atomic weights, or that any atomic weight is not merely a mean number.
The elements which are the most widely diffused have small atomic weights.
Certain characteristic properties of elements can be foretold from their atomic weights.
The elements, if arranged according to their atomic weights, exhibit an apparent periodicity of properties.
If all the elements are arranged in the order of their atomic weights, a periodic repetition of properties is obtained. This is expressed by the law of periodicity.
Since it is proposed to regard chemical reactions as electrical transactions in which reagents act by reason of a constitutional affinity either for electrons or for atomic nuclei, it is important to be able to recognize which type of reactivity any given reagent exhibits.
Experimental work of great refinement is necessary in order to determine atomic weights. No relationships between them have yet been certainly found which make it possible for us to compute by any sort of calculation exactly the value of any one atomic weight from any other.
The question whether atoms exist or not... belongs rather to metaphysics. In chemistry we have only to decide whether the assumption of atoms is an hypothesis adapted to the explanation of chemical phenomena... whether a further development of the atomic hypothesis promises to advance our knowledge of the mechanism of chemical phenomena... I rather expect that we shall some day find, for what we now call atoms, a mathematico-mechanical explanation, which will render an account of atomic weight, of atomicity, and of numerous other properties of the so-called atoms.
That which had grown from the earth, to the earth, But that which has sprung from heavenly seed, Back to the heavenly realms returns. This is either a dissolution of the mutual involution of the atoms, or a similar dispersion of the unsentient elements.
On the geometric level, we see certain physical elements repeated endlessly, combined in an almost endless variety of combinations. It is puzzling to realize that the elements, which seem like elementary building blocks, keep varying, and are different every time that they occur. If the elements are different every time that they occur, evidently then, it cannot be the elements themselves which are repeating in a building or town; these so-called elements cannot be the ultimate "atomic" constituents of space.
When the elements are arranged in vertical columns according to increasing atomic weight, so that the horizontal lines contain analogous elements again according to increasing atomic weight, an arrangement results from which several general conclusions may be drawn.
Radioactivity is shown to be accompanied by chemical changes in which new types of matter are being continually produced. .... The conclusion is drawn that these chemical changes must be sub-atomic in character.
Perhaps that is nearly the perfection of good writing which is original, but whose truth alone prevents the reader from suspecting that it is so; and which effects that for knowledge which the lens effects for the sunbeam, when it condenses its brightness in order to increase its force.
Alchemy is about the generation of a psychic construct, a wholeness, a thing which has many properties, which is paradoxical, which is both mind and matter, which can do anything.
For the elements have the property of moving back to their place in a straight line, but they have no properties which would cause them to remain where they are, or to move otherwise than in a straight line. The rectilinear motions of these four elements when returning to their original place are of two kinds, either centrifugal, viz., the motion of the air and the fire; or centripedal, viz., the motion of the earth, and the water; and when the elements have reached their original place, they remain at rest.
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