Dmitri Mendeleev Quotes

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).

Certain characteristic properties of elements can be foretold from their atomic weights.

Everywhere in the universe, the periodic table has the same basic structure. Even if an alien civilization's table weren't plotted out in the castle-with-turrets shape we humans favor, their spiral or pyramidal or whatever-shaped periodic table would naturally pause after 118 elements.

The magnitude of the atomic weight determines the character of the element, just as the magnitude of the molecule determines the character of a compound body.

The elements, if arranged according to their atomic weights, exhibit an apparent periodicity of properties.

I still have a vivid memory of my excitement when I first saw a chart of the periodic table of elements. The order in the universe seemed miraculous.

In some sense, what you might have suspected from the first day of high-school chemistry is true: The periodic table is a colossal waste of time. Nine out of every 10 atoms in the universe are hydrogen, the first element and the major constituent of stars. The other 10 percent of all atoms are helium.

I still have a vivid memory of my excitement when I first saw a chart of the periodic table of elements.

Thus at the beginning of 1906 it seemed to be established that the emitters of the spectral series of chemical elements are their positive atomic ions.

About seven years later I was given a book about the periodic table of the elements. For the first time I saw the elegance of scientific theory and its predictive power.

Atoms of Element 118 fill an outer shell with electrons, creating a special type of element called a noble gas. Noble gases are natural turning points on the table, ending one row and pointing to the next.

Over the years, humans have managed to incorporate nearly every element, light and weighty, common and obscure, into our daily lives. And given how small atoms are and how many of them there are all around us, it's almost certain that your body has at least brushed against an atom of every single natural element on the periodic table.

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.

The discovery of various phenomena has led to a recognition of the fact that the chemical atom is an individual which again is itself made up of several units into a selfcontained whole.

If you had to sum up chemistry in one sentence, it might be this: Atoms need to have full shells of electrons to feel satisfied, and different elements steal, shed, or borrow different numbers of electrons to achieve a full shell.

The body tends to treat elements in the same column of the periodic table as equivalents.

Boron is carbon's neighbor on the periodic table, which means it can do a passable carbon impression and wriggle its way into the matrix of a diamond. But it has one fewer electron, so it can't quite form the same four perfect bonds.

In chemical terms, radium differs little from barium; the salts of these two elements are isomorphic, while those of radium are usually less soluble than the barium salts.

[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.

If you memorize the periodic table it will speed you up if you're a chemist, but by and large, the reason you have a periodic table is so that you can store that information outside of your body. That way it frees up some part of your brain to do something else...

Moreover, the abundance of chemical compounds and their importance in daily life hindered the chemist from investigating the question, in what does the individuality of the atoms of different elements consist.

It is more likely that more than a century will pass before we know the structure of the chemical atoms as thoroughly as we do our solar system.

We must expect the discovery of many as yet unknown elements-for example, elements analogous to aluminum and silicon- whose atomic weight would be between 65 and 75.

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.

It has long been known that the chemical atomic weight of hydrogen was greater than one-quarter of that of helium, but so long as fractional weights were general there was no particular need to explain this fact, nor could any definite conclusions be drawn from it.