Metals may unite chemically both with metals and with non-metals.
To obtain the metal chemically pure a specially prepared pure oxide or salt of zinc is distilled.
Chemically related to vanadium are the two elements tantalum and columbium or niobium.
Jacob Joseph Winterl, in 1788, appears to have been the first to examine petroleum chemically, but the earliest systematic investigation was that carried out by Professor B.
Chemically pure sodium nitrate can be obtained by repeated recrystallization of Chile saltpetre or by synthesis.
Specimens of the best known and of many of the lesser known rubbers are included in the Colonial and Indian Collections and Sample Rooms of the Imperial Institute, and many of the authentic specimens have been chemically and technically examined in the Scientific and Technical Department of the Institute and commercially valued.
It is very similar to strychnine, both chemically and physiologically.
Lord Rayleigh in 1894 found that the density of atmospheric nitrogen was about 2% higher than that of chemically prepared nitrogen, a discovery which led to the isolation of the rare gases of the atmosphere.
Like H 2 O, CO 2 is a chemically inert molecule.
The alluvial extracted, which in the Malay Peninsula and Archipelago carries from 5 to 60 lb of tinstone (or "black tin," as it is termed by Cornish miners) to the cubic yard of gravel, is washed in various simple sluicing appliances, by which the lighter clay, sand and stones are removed and tinstone is left behind comparatively pure, containing usually 65 to 75% of metallic tin (chemically pure tinstone contains 78.7%).
This operation is no doubt intended to remove the oxygen diffused throughout the metal as oxide, part of it perhaps chemically by reduction of the oxide to metal, the rest by conveying the finely diffused oxide to the surface and causing it to unite there with the oxide scum.
Of the several commercial varieties Banka tin is the purest; it is indeed almost chemically pure.
GUNCOTTON, an explosive substance produced by the action of strong nitric acid on cellulose at the ordinary temperature; chemically it is a nitrate of cellulose, or a mixture of nitrates, according to some authorities.
Great importance was also attached to chemically prepared remedies as containing the essence or spiritual quality of the material from which they were derived.
In regard to gold this has been proved to be so; gold leaf, or thin films of gold produced chemically on glass plates, transmit light with a green colour.
A method of recording signals in the Morse code, formerly used to a considerable extent, was to use a chemically prepared ribbon of paper.
When carbon dioxide is passed into this solution the whole of the added oxide, and even part of the oxide of the normal salt, is precipitated as a basic carbonate chemically similar, but not quite equivalent as a pigment, to white lead.
Uranium is chemically related to chromium, molybdenum and tungsten.
chemically; while, in most living things, mere hetero geneity is exchanged for a definite structure, whereby the body is distinguished into visibly different parts, which possess different powers or functions.
Other isomorphously related elements and groups were soon perceived, and it has been shown that elements so related are also related chemically.
On the other hand, infinitely thin films of silver which can be produced chemically on glass surfaces are absolutely opaque.
Thus, for instance, chemically pure iron in the ingot has the specific gravity 7.844; when it is rolled out into thin sheet, the value falls to 7.6; when drawn into thin wire, to 7.75.
Chemically it is one of the most interesting substances known, since it is the parent of the enormous number of compounds styled the " aromatic " or " benzenoid " compounds.
Chemically they appear to be ether anhydrides of the hexoses, the union being effected by the aldehyde or alcohol groups, and in consequence they are related to the ethers of glucose and other hexoses, i.e.
It is chemically related to cadmium and mercury, the resemblance to cadmium being especially well marked; one distinction is that zinc is less basigenic. Zinc is capable of isomorphously replacing many of the bivalent metals - magnesium, manganese, iron, nickel, cobalt and cadmium.
The simple distillation of sea-water, and the production thereby of a certain proportion of chemically fresh water, is a very simple problem; but it is found that water which is merely evaporated and recondensed has a very disagreeable flat taste, and it is only after long exposure to pure atmospheric air, with continued agitation, or repeated pouring from one vessel to another, that it becomes sufficiently aerated to lose its unpleasant taste and smell and become drinkable.
Many electrolytic methods have been proposed for the purification of sugar; in some of them soluble anodes are used for a few minutes in weak alkaline solutions, so that the caustic alkali from the cathode reaction may precipitate chemically the hydroxide of the anode metal dissolved in the liquid, the precipitate carrying with it mechanically some of the impurities present, and thus clarifying the solution.
We thus learn that the bronzes referred to above, although chemically uniform when solid, are not so when they begin to solidify, but that the liquid deposits crystals richer in copper than itself, and therefore that the residual liquid becomes richer in tin.
The slimes are treated chemically for the separation of the metals contained in them.
Hampe prepared chemically pure bismuth by fusing the metal with sodium carbonate and sulphur, dissolving the bismuth sulphide so formed in nitric acid, precipitating the bismuth as the basic nitrate, redissolving this salt in nitric acid, and then precipitating with ammonia.
Heavy blanks have also been reduced chemically by making them part of the anode in a cyanide bath through which a current of electricity is passed.
His analytical skill enabled him to demonstrate the inaccuracy of the researches by which Berthollet attempted to support the opposite view, and to show among other things that some of the compounds which Berthollet treated as oxides were in reality hydrates containing chemically combined water, and the upshot was that by 1808 he had fully vindicated his position.
The metal is very reactive chemically.
Chemically, it is thus indentical with the cubic mineral diamond, but between the two there are very wide differences in physical characters.
Chemically pure chloride of potassium is most conveniently prepared from the pure perchlorate by heating it in a platinum basin at the lowest temperature and then fusing the residue in a wellcovered platinum crucible.
Chemically it is methyl-tetrahydro-nicotinic acid.
Chemically it is the methyl ester of arecaidine.
The complex fat of the myelin becomes altered chemically, while the other components of the sheath break down.
As it descends it reaches a part of the kiln where the temperature is higher; here the carbonic acid of the carbonate of lime, and the combined water of the clay are driven off, and the resulting lime begins to act chemically on the dehydrated clay.
This destructive action is increased if the water contains sulphates or magnesium salts, both of which act chemically on the calcareous constituents of the cement.
This may be almost chemically pure, when it is generally used for Keene's cement; or it may contain smaller or greater quantities of impurities, in which case it is suitable for the preparation of cements of the plaster of Paris class.
As an elementary substance, it is very similar in its physical properties to lead; it resembles lead chemically inasmuch as it forms an almost insoluble chloride and an insoluble iodide.
Under the head of notion are considered, firstly, the subjective forms of conception, judgment and syllogism; secondly, their realization in objects as mechanically, chemically or teleologically constituted; and thirdly, the idea first of life, and next of science, as the complete interpenetration of thought and objectivity.
It always contains a certain quantity of chemically combined water and also an excess of lime.
For this purpose they are made by Moscicki in the form of glass tubes partly coated by silver chemically deposited on the glass on the inner and outer surfaces.
Chemically the sweet sherry differs from the natural dry light wines in that it contains relatively high proportions of alcohol, extractives, sugar and sulphates, and small quantities of acid and glycerin.
One of the first discoveries made with it was its power to electrolyse or chemically decompose certain solutions.
The municipality owns its waterworks, the water being obtained from eleven artesian wells, and being chemically similar to that of Waukesha Springs.
throughout the year, and the atmosphere is both chemically and optically of singular purity.
chemically or physically.
==Zinc== Chemically the ores of zinc consist of the silicates, carbonates, oxides, and sulphides of zinc associated with other metals, some of which complicate the methods of assay.
The anode residue is collected in the angular bottom of the tank, the electrolyte passes from the anode chamber to a series of tanks in which the more electro-negative constituents (silver, &c.) are chemically separated, and thence to the cathode chamber, where the copper is deposited electrolytically, thence it passes again to the anode chamber and so completes the cycle.
Stas, in his stoichiometric researches, prepared chemically pure bromine from potassium bromide, by converting it into the bromate which was purified by repeated crystallization.
Phosphorus tribromide, PBr 3, prepared by mixing solutions of its elements in carbon disulphide and distilling, is a transparent, mobile liquid, boiling at 173° and resembling the trichloride chemically.
Iron is very reactive chemically.
Chemically, oil of turpentine is a more or less complex mixture of hydrocarbons generically named terpenes.
Here it need only be said that the masses of vegetable substance, more or less carbonized and chemically altered, of which coal is composed, frequently contain cells and fragments of tissue in a condition recognizable under the microscope, as for example spores (sometimes present in great quantities), elements of the wood, fibres of the bark, &c. These remnants, however, though interesting as revealing something of the sources of coal, are too fragmentary and imperfect to be of any botanical importance.
(early in the 19th century) that plants owe their H remedial and poisonous qualities to small quantities of definite active principles, such as alkaloids and neutral bodies, which can be extracted in a chemically pure condition, had also a very important effect on its development.
Bodies which have a close resemblance in their chemical constitution exhibit a similar resemblance in their pharmacological action, and as the constitution of the substance becomes modified chemically so does its action pharmacologically.
The objection to a strictly chemical classification is, that while many substances closely allied chemically have a somewhat similar action in certain respects, yet in others they differ very widely - a striking example of which is given in the case of sodium and potassium.
The resins when taken internally have much the same action as essential oils, which are closely allied chemically, while the benzoic and cinnamic acids in the balsams modify their actions very slightly.
Although individual essential oils may differ somewhat in action, chemically and pharmacologically they are fundamentally similar.
- This includes a very large number of bodies chemically allied to benzol, such as carbolic acid, sulphocarbolates, creosote, wood tar, coal tar, oil of cade, thymol, salicylic acid, benzoic acid, naphthol, hydroquinon, cresol, guaiacol, ichthyol, saccharin and many others.
alumina substrates can also be used to produce chemically stable, strongly hydrophobic surfaces.
Free living barnacle larvae are chemically attracted to barnacle larvae are chemically attracted to barnacle shells and tend to settle among established adults.
Chemically enhanced bentonites have been proposed to overcome the shortcomings of conventional bentonites.
We are interested in expanding the repertoire of biocatalytic reactions by developing novel biocatalysts for reactions that are chemically very difficult.
biocompatible materials to use to reduce toxicity for everyone, especially the chemically sensitive.
Researchers chemically modified adrenaline to find molecules that would have the same effect in dilating the bronchioles but without the stimulation of the heart.
Another option would be to process chemically using caustic soda.
Produce chemically engraved metal plates, chemical milled components and printed circuit boards with the production equipment manufactured by Fortex.
A standard copper strip was taken, the original formed leg terminals were cut off and the new design chemically etched.
fluorescelecule consists of a photochromic moiety chemically bonded to a strongly fluorescing dye.
dry gypsum, with no free moisture, contains 21% chemically bonded water by weight (Thomas 2002 ).
Alumina substrates can also be used to produce chemically stable, strongly hydrophobic surfaces.
inactivate attempts to make one by chemically inactivating the toxin failed.
Members noted that mutations are found in all chemically induced cancers.
The surface properties will be controlled by chemically grafting monolayers with different functional groups on the outer surface.
These microbes absorb the soluble nutrients and exude enzymes to chemically breakdown the material further.
Socio-economic formations never appear in a chemically pure form.
The recent SPADE campaign provided a wealth of high time resolution data on a very large number of chemically reactive species.
But if you add charge carriers by chemically doping them they become superconductors with transition temperatures of up to 135K.
Antigenic molecules will be chemically synthesized from peptides on a ' scaffold ' to help hold them in a correct position.
Mechanisms of action of chemically modified tetracyclines in bone resorption and formation.
Lord Rayleigh in 1894 found that the density of atmospheric nitrogen was about 2% higher than that of chemically prepared nitrogen, a discovery which led to the isolation of the rare gases of the atmosphere (see Argon).
Kohlrausch has prepared water of which the conductivity compared with that of mercury was only o 4 oX 11 at 18Ã‚° C. Even here some little impurity was present, and the conductivity of chemically pure water was estimated by thermodynamic reasoning as o 36X1011 at 18Ã‚° C. As we shall see later, the conductivity of very dilute salt solutions is proportional to the concentration, so that it is probable that, in most cases, practically all the current is carried by the salt.
From these and other considerations it is obvious that (I) the electrolyte must be such as will freely dissolve the metal to be refined; (2) the electrolyte must be able to dissolve the major portion of the anode, otherwise the mass of insoluble matter on the outer layer will prevent access of electrolyte to the core, which will thus escape refining; (3) the electrolyte should, if possible, be incapable of dissolving metals more electro-negative than that to be refined; (4) the proportion of soluble electro-positive impurities must not be excessive, or these substances will accumulate too rapidly in the solution and necessitate its frequent purification; (5) the current density must be so adjusted to the strength of the solution and to other conditions that no relatively electro-positive metal is deposited, and that the cathode deposit is physically suitable for subsequent treatment; (6) the current density should be as high as is consistent with the production of a pure and sound deposit, without undue expense of voltage, so that the operation may be rapid and the "turnover" large; (7) the electrolyte should be as good a conductor of electricity as possible, and should not, ordinarily, be altered chemically by exposure to air; and (8) the use of porous partitions should be avoided, as they increase the resistance and usually require frequent renewal.
The plant, on the other hand, if it be a green plant, containing chlorophyll, is capable, in the presence of light, of building up both carbohydrate material and proteid material from inorganic salts; if it be a fungus, devoid of chlorophyll, whilst it is dependent on pre-existing carbohydrate material and is capable of absorbing, like an animal, proteid material as such, it is able to build up its proteid food from material chemically simpler than proteid.
Chemically pure carbonate of potash is best prepared by igniting pure bicarbonate (see below) in iron or (better) in silver or platinum vessels, or else by calcining pure cream of tartar.
The temperature is uniformly 54Ã‚° Fahr., and the atmosphere is optically and chemically pure.
Phosphorus tribromide, PBr 3, prepared by mixing solutions of its elements in carbon disulphide and distilling, is a transparent, mobile liquid, boiling at 173Ã‚° and resembling the trichloride chemically.
There are several materials now in use possessing remarkable power to decolourize clarify, chemically purify and oxidize water; but they are too costly for use in connexion with public water supplies unless a rate of filtration is adopted quite inconsistent with the formation of a surface film capable of arresting micro-organisms. This fact does not render them less useful when applied to the arts in which they are successfully employed.
Of the 71 eggs obtained, 22 eggs were chemically stimulated to develop parthenogenetically, and 19 were used for nuclear transplant cloning.
We offer an alternative to mass produced, chemically infused, and sweatshop labor products.
Subsequent erosion of the chemically weathered granite took place as a generally radial drainage network evolved around the granite dome.
By 1997, every food was free of added refined sugars and chemically modified starches.
Most power washers are also sold complete with a detergent tank which means that cleaning solutions can be added to the water to chemically clean a surface.
This means that the company has created foods that are not chemically enhanced and are made from the purest ingredients.
Chemically, they're very similar to the cholesterol found in meat products and dairy.
Most of us who see the tell tale signs of gray hair would rather seek out gray hair natural remedies than use chemically designed treatments.
If you have no artistic inclination whatsoever, or are chemically sensitive to the ingredients in puffy paint, personalized makeup bags can be easily purchased.
Ask that the lawns be chemically treated for insects.
The Addiction Medical Group Inc. (AMGI) offers Rapidly Accelerated Narcotic Detoxification (a.k.a. ultrarapid opiate detoxification) to people who are chemically dependent on opiates.
AH: Fabric can either be chemically or mechanically conditioned, or not at all.
Why, one might almost jump to the conclusion that her accident-prone behavior might be chemically induced-then again, she could just be going through an awkward phase.
While heat treated stones are not necessarily inferior to natural stones, people wanting a completely natural stone may prefer not to have one that has been chemically altered.
Unless it's been chemically treated, it keeps you warm and also breathes, keeping moisture at bay.
Conversely, many vitamins and supplements are chemically made or formed from chemically derived ingredients.
For instance, coffee is one of the most heavily chemically treated food products in the world.
Organic lawn care utilizes different methods that have less of an environmental impact than chemically based lawn care products.
Like grapes, strawberries are very susceptible to mold and are therefore one of the most heavily chemically treated fruits in the country.
The chemical residue left behind after plants are chemically treated creates problems too.
The raising and shearing of the sheep is often inhumane and the wool is then chemically treated, which can be bad for your skin.
Increased dopamine levels were detected, confirming some experts' opinion that gaming is chemically addictive.
Unlike the plastic build quality of the iPhone 3GS, Apple crams all of the internal components into two chemically treated glossy slabs of aluminosillicate glass.
Decongestant drugs are chemically similar to epinephrine and norepinethrine, which are hormones that cause excitation in the body.
Cocaine is chemically different from the traditional stimulants but provides similar effects.
The test uses a strip or disc that is chemically coated with an antibody specific for the strep antigen.
These drugs are chemically related and have similar uses, but because they are distributed differently in the body, they may be used for different purposes.
These medications may be lotions, ointments, or plasters and work by chemically removing the skin that was affected by the wart virus.
They work together synergistically and must be chemically balanced in the body; if one is deficient or out of balance, it can affect all the others, often resulting in illness.
There are several antidepressants available as of 2004 that, because they are not chemically structured like the other types of antidepressants, are grouped into the category "other" or miscellaneous.
Pediculicides can be poisonous if used improperly or too frequently and overuse can lead to the proliferation of chemically resistant lice.
The fluoroquinolones, which are based on the older group, are broad-spectrum bactericidal drugs that are chemically unrelated to the penicillins or the cephalosporins.
If you have your hair chemically relaxed, make sure you discuss the best shampoos and conditioners for your situation with your stylist; some leading black hair stylists recommend Nexxus hair products as well as the Dudley product line.
This hair may have been colored or chemically treated to alter its texture.
They use hair that has never been colored or chemically processed, so the hair's cuticle is fully intact.
One style you typically don't see in emo styles, however, is mechanically or chemically created curls.
The fortetherapie line focuses on strengthening chemically stressed or damaged hair with infusions of lemongrass and mango.
However, if one has extremely fair colored strands or chemically processed hair that exhibits damage to the cuticle, semi-permanent color may be absorbed deep into the hair shaft, resulting in a more lingering color.
The Frederic Fekkai technician products are intended to treat very dry chemically processed hair.
People with extremely chemically processed hair should use this product no more than once-weekly as it is very clarifying and can result in dry hair.
This shampoo is safe for both natural and chemically enhanced hair, and it comes complete with a delectable almond scent.
Chemically treated hair often looks dry and sick.
Hair cannot be chemically damaged or bleached, and it cannot be swept off a salon floor (the alignment will be destroyed).
Keep in mind that permed or chemically processed hair is more porous than untreated hair types and, therefore, color may not be absorbed evenly.
This hair product is only able to aid the maintenance of chemically damaged hair by coating the cuticle, therefore making the hair less prone to breakage.
As mentioned before, chemically damaged hair has damaged the natural protein structure of the hair.
For people with severely broken or chemically dried-out hair, this hair care collection will probably produce the most immediate results.
Frederic Fekkai also has a Technician Line that is intended for merely dry, chemically processed hair.
The Childhood Leukemia Foundation accepts hair that's ten inches long, but it can't be colored or chemically damaged.
Children With Hair Loss only requires hair to be eight inches long, and while they prefer the hair not to be chemically treated, as long as it's still in good condition, they will accept it.
They can't use colored or chemically treated hair.
Chemically Damaged Hair: Making a wig can be stressful on the hair, and severely damaged hair is often too brittle to withstand the manufacturing process.
If your hair has previously been chemically treated, you'll need to fess up to your stylist so they can bear in mind any major challenges they may face while working on your desired shade.
Protein treatments will drastically improve the condition of chemically treated hair, so make this quality product a must on your beauty list!
Banks does not have an afro; rather her shoulder length locks, which she claims are not chemically treated, were blown out and styled by a professional to make them appear healthy, shiny, and curvy, not kinky.
Avoid color: If you really want rapid hair growth, you'll notice much more of a difference if you stop chemically treating or coloring your hair.
Thin hair, for instance, typically becomes even limper when some conditioners are applied, while chemically treated hair may require extra nourishment to prevent damage.
The fragrance, preservatives, foaming agents and many other ingredients are likely to have come from chemically derived sources.
Often used in spas for its tolerance of high pH levels and temperatures, bromine is in the same family of chemicals as chlorine, and chemically speaking, is very similar in structure.
The fabric might be chemically treated, making the skin more prone to rashes.
If you regularly take a dip in a chemically treated swimming pool, over time your suit will begin to deteriorate.
Chemically, sodium bicarbonate is a base.
Since many women with black hair also regularly use heat appliances, relaxers that chemically straighten hair, and hair coloring; black hair requires extra care to keep it healthy looking and strong.
The wax can be chemically cleaned and prepared.
While commercially prepared beeswax is often bleached and chemically refined, this simple form of filtering the wax to clean it provides a natural form of beeswax that is perfect for making candles in their most natural form.
Colored hair cannot be accepted if it is dyed with permanent color, is bleached or chemically treated.
Cultured diamonds, because they are grown in a chemically controlled environment, are also much more likely to be flawless and structurally perfect than natural stones.
Value - Our real, certified diamonds are physically, chemically and optically identical to earth-mined diamonds only less expensive in fancy colors.
The end result is a "diamond in the rough," which is physically, chemically and optically identical to an earth-mined diamond.
Arguably, the easiest way to clean black chalkboards is to use a chemically treated chalkboard cloth.
These special cleaning cloths are chemically treated and last approximately a year.
These chemically altered ingredients are the culprits for the change in taste and texture of many foods in comparison to the full fat version.
Herbs are considered natural because they grow from the earth versus being chemically made in a factory.
Trans fat: These fats are chemically engineered and are used to hydrogenate oils.
Despite the claim that only certain foods interact chemically to burn fat, the only similarities between these two plans are that both menus make use of low calorie common diet foods while neglecting needed nutrients and fiber.
The end menu plan is designed to feed the body the freshest, chemically free foods available prepared in interesting delicious ways to tempt the palate.
Complex carbs, on the other hand, are more complex, chemically.
When the rash is chemically induced, you should pay attention to its possible cause so that you know how to avoid it in future.
Fading creams work by chemically lightening the skin.
This fruit based acid chemically burns away dead skin cells and any sebum built up underneath it.
One remarkable discovery, however, of general interest, was the outcome of a long series of delicate weighings and minute experimental care in the determination of the relative density of nitrogen gas - undertaken in order to determine the atomic weight of nitrogen - namely, the discovery of argon, the first of a series of new substances, chemically inert, which occur, some only in excessively minute quantities, as constituents of the 1 The barony was created at George IV.'s coronation in 1821 for the wife of Joseph Holden Strutt, M.P. for Maldon (1790-1826) and Okehampton (1826-1830), who had done great service during the French War as colonel of the Essex militia.
The peculiar substance called callose, chemically allied to cellulose, is frequently formed over the surface of the perforated end-walls.
The chloro-bromide and bromide of silver were also included under this term until they were distinguished chemically in 1841 and 1842, and described under the names embolite and bromargyrite (or bromyrite) respectively; the chloride then came to be distinguished as chlorargyrite, though the name cerargyrite is often now applied to this alone.
the force which holds chemically dissimilar substances together (and also similar substances as is seen in di-, tri-, and poly-atomic molecules), was introduced by Hermann Boerhaave, and made more precise by Sir Isaac Newton.
isomerism, or the existence of two or more chemically different substances having identical molecular weights, is adequately shown; and, most important of all, once the structure is determined, the synthesis of the compound is but a matter of time.
Isomorphism may be defined as the existence of two or more different substances in the same crystal form and structure, polymorphism as the existence of the same substance in two or more crystal modifications, and morphotropy (after P. von Groth) as the change in crystal form due to alterations in the molecule of closely (chemically) related substances.
It is not at all certain that the masses on which coral reefs are built consist entirely of the remains of the skeletons of reef-forming organisms and it is probable that chemically precipitated carbonate of lime predominates.
Chemically they resemble the albumins, being split up by acids or ferments into albumoses, peptones and amino-acids, forming salts, and giving N =C6 1 The pyrimidin ring is numbered 2C "C5.
Now this ratio is the same as that which gives the relative chemical equivalents of hydrogen and copper, for r gramme of hydrogen and 31.8 grammes of copper unite chemically with the same weight of any acid radicle such as chlorine or the sulphuric group, SO 4.
Kohlrausch has prepared water of which the conductivity compared with that of mercury was only o 4 oX 11 at 18° C. Even here some little impurity was present, and the conductivity of chemically pure water was estimated by thermodynamic reasoning as o 36X1011 at 18° C. As we shall see later, the conductivity of very dilute salt solutions is proportional to the concentration, so that it is probable that, in most cases, practically all the current is carried by the salt.
If some of the anions, instead of being simple iodine ions represented chemically by the symbol I, are complex structures formed by the union of iodine with unaltered cadmium iodide - structures represented by some such chemical formula as I(CdI 2), the concentration of the solution round the anode would be increased by the passage of an electric current, and the phenomena observed would be explained.
We may take it, then, that only that portion of these bodies is chemically active which is electrolytically active - that ionization is necessary for such chemical activity as we are dealing with here, just as it is necessary for electrolytic conductivity.
by determining the rotation of the plane of polarization of a solution, or, chemically, by taking advantage of its property of reducing alkaline copper solutions.
This can only be effected if the surface of the metal on which the deposit is to be made is chemically clean.
For the preparation of chemically pure tin two methods are employed.
Chemically pure sand is silicon dioxide (SiO 2) or quartz, a clear transparent glass-like mineral, but as ordinarily met with, it is more or less impure and generally coloured reddish or yellowish by oxide of iron.
A redistilled zinc, from an ordinarily pure commercial zinc, is often called chemically pure, but redistillation is seldom practised except for the recovery of zinc from galvanizer's dross and from the skimmings and bottoms of the melting furnaces of zinc rolling mills.
In 1902, in an "attempt at a chemical conception of the ether," he put forward the hypothesis that there are in existence two elements of smaller atomic weight than hydrogen, and that the lighter of these is a chemically inert, exceedingly mobile, all-penetrating and all-pervading gas, which constitutes the aether.
The oil has been chemically analysed and found to be a fish-oil, and to possess nearly all the qualities of that obtained from the liver of the cod, with a lighter specific gravity.
The temperature is uniformly 54° Fahr., and the atmosphere is optically and chemically pure.
Storage for eight months did not disturb the density of the chemically extracted gas, nor had the silent electric discharge any influence upon either quality.
To these is added water, which combining chemically with the cement conglomerates the whole mixture into a solid mass, and forms a rough but strong artificial stone.
It should be free from dirt - that is to say, free from clay or soft mud, for instance, which prevents the cement adhering to its particles, or again from sewage matter or any substance which will chemically destroy the matrix.
The amount required to combine chemically with the cement is about 16% by weight, but in practice much more than this is used, because of loss by evaporation, and the difficulty of ensuring that the water shall be uniformly distributed.
Its electrical conductivity, determined on 99.6% metal, is 60.5% that of copper for equal volumes, or double that of copper for equal weights, and when chemically pure it exhibits a somewhat higher relative efficiency.
The individual and collective influence of the several impurities which occur in the product of the Heroult cell is still to seek, and the importance of this inquiry will be seen when we consider that if cast iron, wrought iron and steel, the three totally distinct metals included in the generic name of "iron" - which are only distinguished one from another chemically by minute differences in the proportion of certain non-metallic ingredients - had only been in use for a comparatively few years, attempts might occasionally be made to forge cast iron, or to employ wrought iron in the manufacture of edge-tools.
The Ores actually Impure.-As these five minerals actually exist in the earth's crust they are usually more or less impure chemically, and they are almost always mechanically mixed with xlv.
Its physical and chemical properties have been the subject of much study, and have a special interest in view of the extraordinary difference between the physical characters of the diamond and those of graphite (blacklead) or charcoal, with which it is chemically identical, and into which it can be converted by the action of heat or electricity.
When chemically pure, which is rarely the case, blende is colourless and transparent; usually, however, the mineral is yellow, brown or black, and often opaque, the depth of colour and degree of transparency depending on the amount of iron present.
Thus Japan wax is a glyceride and should be more correctly termed Japan tallow, whereas sperm oil is, chemically speaking, a wax.
The word usage examples above have been gathered from various sources to reflect current and historial usage. They do not represent the opinions of YourDictionary.com.