Basic substances

Crude oils contain nitrogen compounds in the form of basic substances such as quinoline, isoquinoline, and pyridine, or neutral materials such as pyrrole, indole, and carbazole. 

An amino-acid, although insoluble in water (e.g., anthranilic acid), is usually soluble in excess of mineral acid in such a case it is important to make the solution only very slightly acid. This applies also to a mixture of a neutral and a basic substance, from which dil. HCl will extract an amino-acid the solution must then be carefully treated with NaOH to precipitate the amino-acid. 

Various basic substances, such as aromatic amines (naphthyl-amines dissolve with difficulty in dil. HCl, diphenylamine only in cone. HCl, triphenylamine insoluble) nitro-anilines some amino-carboxylic acids. 

Dilute hydrochloric or sulphuric acid finds application in the extraction of basic substances from mixtures or in the removal of basic impurities. The dilute acid converts the base e.g., ammonia, amines, etc.) into a water-soluble salt e.g., ammonium chloride, amine hydrochloride). Thus traces of aniline may be separated from impure acetanilide by shaking with dilute hydrochloric acid the aniline is converted into the soluble salt (aniline hydrochloride) whilst the acetanilide remains unaffected. 

The mechanism of the aromatic substitution may involve the attack of the dectrophilic NOj" " ion upon the nucleophilic aromatic nucleus to produce the carboniiim ion (I) the latter transfers a proton to the bisulphate ion, the most basic substance in the reaction mixture... 

Basic substances for standardizing acidic solutions continued)... 

The obtained analytical forms are used for quantitative determination of both Diclofenac natrium and Ibuprofen content in medicinal forms as well as for the testing uniformity of batching of the basic substance in tableted forms. The relative standard deviation (RSD) were 3,7-4,6 % (n = 5 P = 0,95). 

Basic materials such as lime or magnesium oxide increase the hardening rate of novolak-hexa compositions and are sometimes referred to as accelerators. They also function as neutralising agents for free phenols and other acidic bodies which cause sticking to, and staining of, moulds and compounding equipment. Such basic substances also act as hardeners for resol-based compositions. 

Acidic and basic substances can be detected using pH indicators. Indicators changing color in the acid region are primarily employed. They are apphed to the chromatogram by dipping or spraying with 0.01 to 1% solutions. The pH is... 

A second basic substance isolated from papaw seed and named car-pasemine has been shown to be benzylthiourea. ... 

The oxidation products of pseudaconitine have been investigated by Henry and Sharp. With chromic acid it yields a weakly basic substance, C34H 50] ] N, prisms, m.p. 255° (dec.), + 67-95°, which forms unstable... 

The hexahydro derivatives are weakly basic substances, some of them forming hydrochlorides. Dioxohexahydrotriazine yields a 1,5-diacetyl derivative (35), in which the positions of the acetyl groups were determined by acetylation of the A-alkyl derivatives and methylation with diazomethane according to Scheme 4. ... 

Grund-sebicht, /. primary layer, fundamental layer ground course, -stein, m. foundation stone, cornerstone lower (mill) stone, -stock, m. matrix, -stoff, m. element raw material base Paper) ground pulp, -stofflndustrie, /. basic industry, -stoff-wechsel, m. basal metabolism, -stricb, m. first coat, priming down stroke, -stuck, m. premises, (real) property. -substanz, /. element basic substance Anat.) ground substance, matrix, -teil, m. element, principle basic part, -teilcben, n. fundamental particle, -ton, m. fundamental tone, primary tone, -umsatz, m. Biol.) basal metabolism. 

The ending -in should be translated -ine in the case of basic substances and -in elsewhere as, aniline, glycine, palmitin, albumin. (But for names of alcohols see (2)). 

The mixture is then slowly heated to the boiling point of toluene and kept boiling for one hour under reflux. After the mixture has been allowed to cool the sodium chloride which precipitates is separated by extraction with water. The solution of toluene is then extracted with dilute hydrochloric acid. From the hydrochloric acid extract the basic substance is separated in the form of an oil by means of caustic soda solution and is introduced into ether. The ethereal solution Is dried with the aid of potassium carbonate and then distilled. 

The methanol in the reaction mixture (pale yellow solution) is then removed by evaporation under reduced pressure to leave a residue which is subsequently dissolved in 30 ml of benzene. The benzene solution is shaken four times with 20 ml of 4 N hydrochloric acid each time to extract the basic substance. Each of the hydrochloric acid layers is washed once with 20 ml of benzene and combined together to be neutralized with potassium carbonate while being ice-cooled until it becomes basic (pH = 10). 

What actually converted me to the left-step table, at least for a period of a few years, was a rather concise paper by the periodic table designer Gary Katz, which appeared in The Chemical Educator.20 My own support for this form of the table centered on my interest in the dual sense of the term element and in particular the more fundamental sense, called element as a basic substance by Paneth. 

What I hope to have added to the discussion has been a philosophical reflection on the nature of the concept of element and in particular an emphasis on elements in the sense of basic substances rather than just simple substances. The view of elements as basic substances, is one with a long history. The term is due to Fritz Paneth, the prominent twentieth century radio-chemist. This sense of the term element refers to the underlying reality that supports element-hood or is prior to the more familiar sense of an element as a simple substance. Elements as basic substances are said to have no properties as such although they act as the bearers of properties. I suppose one can think of it as a substratum for the elements. Moreover, as Paneth and before him Mendeleev among others stressed, it is elements as basic substances rather than as simple substances that are summarized by the periodic table of the elements. This notion can easily be appreciated when it is realized that carbon, for example, occurs in three main allotropes of diamond, graphite and buckminsterfullenes. But the element carbon, which takes its place in the periodic system, is none of these three simple substances but the more abstract concept of carbon as a basic substance. 

Schwarz also makes the interesting identification between neutral atoms and elements as simple substances on one hand, and between bonded atoms and elements as basic substances on the other hand. As a frequent participant at conferences on the philosophy of chemistry, Schwarz seems to have fully grasped the importance of this distinction between the two senses of the macroscopic element. Whether or not his one-to-one identification of the dual sense of an element with microscopic atoms is meaningful remains to be seen, but here I argue that he is mistaken. 

Instead I propose a more radical solution, namely that of not identifying bonded atoms with elements as basic substances, a view for which I claim support from the work of Mendeleev and Paneth. This does not solve the problem of redesigning a periodic table to reflect the behavior of bonded atoms. But if we are to retain the traditional periodic table of neutral atoms, we may still forge a connection with elements as basic substances by arranging the elements so as to maximize atomic number triads, where atomic number may now be interpreted to also mean element number . 

I suggested that we should use the term "basic substance whenever we want to designate that which is indestructible in compounds...and that we should speak of a simple substance when referring to the form in which such a basic substance, not combined with any other, is presented to our senses (3). 

To state the distinction otherwise, simple substances are the manifestation of the elements considered as basic substances, the latter being the more fundamental of the two senses of the term element . Admittedly the terminology is a little unfortunate since the labels basic and simple appear to place the two senses of the term element on the same epistemological level. The intention however is that basic substances are to be regarded as more fundamental. Be that as it may, we will retain Paneth s terminology in view of the importance of the writings of this author in which the distinction is perhaps more clearly established than elsewhere in the literature (5). 

The aim of the present article is to elevate the role of triads to an even greater extent. Since triads are now expressed in terms of atomic numbers they coincidentally characterize the elements as basic substances. In other words they characterize the true basis for periodic classification compared with the elements as simple substances, as argued by Mendeleev and more recently by Paneth and other authors. 

As suggested in the title of the present article, we believe that the periodic table, which initially arose from the discovery of atomic weight triads, can now be further enhanced by recognizing the fundamental importance of atomic number triads. In addition one should recognize the more fundamental nature of the elements as basic substances rather than as simple substances, and that the periodic system is primarily a classification of the former. Whereas we previously suggested that these aims were best served by the left-step table we now favor the revised left-step table shown in Figure 3. 

The new proposed version does not alleviate the concern that some authors voice in wanting to maintain the metals on the left and non-metals on the right of the table. We suggest that such a desideratum does not necessarily reflect the most fundamental aspects of the elements as basic substances whereas the left-step and its new variant do. The latter two forms aim to represent elements as basic substances as well as establishing a closer connection with fundamental aspects of electron-shell filling, and consequently with quantum mechanics, than the medium-long form table does. Finally, we have recently published another new table that differs only in shape from the one proposed here (10). 

ABSTRACT This article concerns various foundational aspects of the periodic system of the elements. These issues include the dual nature of the concept of an "element" to include element as a "basic substance" and as a "simple substance." We will discuss the question of whether there is an optimal form of the periodic table, including whether the left-step table fulfils this role. We will also discuss the derivation or explanation of the [n + , n] or Madelung rule for electron-shell filling and whether indeed it is important to attempt to derive this rule from first principles. In particular, we examine the views of two chemists, Henry Bent and Eugen Schwarz, who have independently addressed many of these issues. 2008 Wiley Periodicals, Inc. Int J Quantum Chem 109 959-971, 2009... 

There has been some discussion as to whether the word "substance" is appropriate in this context. For example, Earley believes it is not because it implies a form of materiality which is not intended [21. In this article, the word "substance" will be used, however, because of the terminology coined by Paneth when he drew his distinction between the two senses of the term "element." However, Paneth actually uses the German words "grundstuff" and "einfacherstuff" which were translated as basic substance and simple substance, respectively, in the article that appeared in the British journal for the Philosophy of Science and which has been most widely read. 

Indeed, the terminology of element as basic substance as opposed to as simple substance, which has been used throughout this article, originates with this work of Paneth. 

However, I believe that Bent s understanding of elements as basic substances is incorrect because he insists on identifying them with neutral atoms of the elements. 

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