From these results Baeyer concluded that Claus' formula with three para-linkings cannot possibly be correct, for the Q2.5 dihydroterephthalic acid undoubtedly has two ethylene linkages, since it readily takes up two or four atoms of bromine, and is oxidized in warm aqueous solution by alkaline potassium permanganate.
From meta-brombenzoicacid two nitrobrombenzoic ac i ds are obtained on direct nitration; elimination of the bromine atom and the reduction of the nitro to an amino group in these two acids results in the formation of the same ortho-aminobenzoic acid.
It combines directly with fluorine at Ordinary temperature, and with chlorine, bromine and sulphur on heating.
With bromine in acetic acid solution at ordinary temperature, nicotine yields a perbromide, C10H10Br2N20 HBr 3, which with sulphur dioxide, followed by potash, gives dibromcotinine, C10H10Br2N20, from which cotinine, C10H12N20, is obtained by distillation over zinc dust.
By heating nicotine with bromine in hydrobromic acid solution for some hours at 100° C., dibromticonine hydrobromide, C10H8N2Br202 HBr, results.
Molybdenum combines with the halogen elements in varying proportions, forming with chlorine a di-, tri-, tetraand penta-chloride, and similar compounds with bromine and iodine.
With ferric chloride it gives a violet coloration, and with bromine water a white precipitate of tribromphenol.
Phenol is characterized by the readiness with which it forms substitution products; chlorine and bromine, for example, react readily with phenol, forming orthoand parachlorand -bromphenol, and, by further action, trichlorand tribrom-phenol.
When heated with bromine and water to too° C. it forms tribromacetic acid, some bromoform being produced at the same time.
Bromine converts it into dibromacrylic acid, and it gives with hydrochloric acid (3-chloracrylic acid.
The elements are usually divided into two classes, the metallic and the non-metallic elements; the following are classed as non-metals, and the remainder as metals: Of these hydrogen, chlorine, fluorine, oxygen, nitrogen, argon, neon, krypton, xenon and helium are gases, bromine is a liquid, and the remainder are solids.
The following, however, are negative towards the remaining elements which are more or less positive:-Fluorine, chlorine, bromine, iodine, oxygen, sulphur, selenium, tellurium.
For instance, 35'45 parts of chlorine and 79.96 parts of bromine combine with 107.93 parts of silver; and when chlorine and bromine unite it is in the proportion of 35'45 parts of the former to 79.96 parts of the latter.
Thus, in the production of hydrochloric acid from hydrogen and chlorine 22,000 calories are developed; in the production of hydrobromic acid from hydrogen and bromine, however, only 8440 caloriesare developed; and in the formation of hydriodic acid from hydrogen and iodine 6040 calories are absorbed.
This difference in behaviour of the three elements, chlorine, bromine and iodine, which in many respects exhibit considerable resemblance, may be explained in the following manner.
In the formation of gaseous hydrobromic acid from liquid bromine and gaseous hydrogen H2+Br2=HBr+HBr, in addition to the energy expended in decomposing the hydrogen and bromine molecules, energy is also expended in converting the liquid bromine into the gaseous condition, and probably less heat is developed by the combination of bromine and hydrogen than by the combination of chlorine and hydrogen, so that the amount of heat finally developed is much less than is developed in the formation of hydrochloric acid.
Thus, chlorine enters into reaction with hydrogen, and removes hydrogen from hydrogenized bodies, far more readily than bromine; and hydrochloric acid is a far more stable substance than hydrobromic acid, hydriodic acid being greatly inferior even to hydrobromic acid in stability.
The discovery of bromine in 1826 by A.
It was long supposed that the simplest ring obtainable contained six atoms of carbon, and the discovery of trimethylene in 1882 by August Freund by the action of sodium on trimethylene bromide, Br(CH 2) 3 Br, came somewhat as a surprise, especially in view of its behaviour with bromine and hydrogen bromide.
In comparison with the isomeric propylene, CH 3 HC:CH 2, it is remarkably inert, being only very slowly attacked by bromine, which readily combines with propylene.
A similar behaviour has since been noticed in other trimethylene derivatives, but the fact that bromine, which usually acts so much more readily than hydrobromic acid on unsaturated compounds,, should be so inert when hydrobromic acid acts readily is one still.
Substitution of the Benzene Ring.-As a general rule, homologues and mono-derivatives of benzene react more readily with substituting agents than the parent hydrocarbon; for example, phenol is converted into tribromphenol by the action of bromine water, and into the nitrophenols by dilute nitric acid; similar activity characterizes aniline.
[2.4.6]-trinitrophenol) into chloropicrin, CCI 3 NO 2, by bleaching lime (calcium hypochlorite), and into bromopicrin, CBr 3 NO 2, by bromine' water.
Bromine water oxidizes this substance to oxalic acid and tetrabromdichloracetone (5).
The elements which play important parts in organic compounds are carbon, hydrogen, nitrogen, chlorine, bromine, iodine, sulphur, phosphorus and oxygen.
Thus bromine and iodine replace chlorine with increments of about 22° and 50° respectively.
The thermal effects of the halogens are: chlorine =15.13 calories, bromine = 7.68; iodine = - 4.25 calories.
When heated with the halogens, acetophenone is substituted in the aliphatic portion of the nucleus; thus bromine gives phenacyl bromide, C6H6CO.CH2Br.
Caoutchouc, like other "unsaturated" molecules, forms compounds with chlorine, bromine, iodine and sulphur.
The Ivanhoe baths, erected in 1826, are frequented for their saline waters, which, as containing bromine, are found useful in scrofulous and rheumatic complaints.
It combines with bromine to form a dibromide, from which E.
Other constituents are cholesterol (0.461.32%), traces of calcium, magnesium, sodium, chlorine and bromine, and various aliphatic amines which are really secondary products, being formed by the decomposition of the cellular tissue.
Orthophosphoric acid, H3P04, a tribasic acid, is obtained by boiling a solution of the pentoxide in water; by oxidizing, red phosphorus with nitric acid, or yellow phosphorus under the surface of water by bromine or iodine; and also by decomposing a mineral phosphate with sulphuric acid.
Chemical methods of sterilization have also been suggested, depending on the use of iodine, chlorine, bromine, ozone, potassium permanganate, copper sulphate or chloride and ()their substances.
Oxidation gives formaldehyde, formic acid and carbonic acid; chlorine and bromine react, but less readily than with ethyl alcohol.
The elements in addition to oxygen which exist in largest amount in sea salt are chlorine, bromine, sulphur, potassium, sodium, calcium and magnesium.
Sorensen and Martin Knudsen after a careful investigation decided to abandon the old definition of salinity as the sum of all the dissolved solids in sea-water and to substitute for it the weight of the dissolved solids in 1000 parts by weight of sea-water on the assumption that all the bromine is replaced by its equivalent of chlorine, all the carbonate converted into oxide and the organic matter burnt.
Acetylene tetrabromide, C 2 H 2 Br 4, which is very conveniently prepared by passing acetylene into cooled bromine, has a density of 3 ooi at 6° C. It is highly convenient, since it is colourless, odourless, very stable and easily mobile.
Since it does not form an addition product with bromine, reduction must have taken place in one of the nuclei only, and on account of the aromatic character of the compound it must be in that nucleus which does not contain the amino group. This tetrahydro compound yields adipic acid, (CH 2) 4 (CO 2 H) 2, when oxidized by potassium permanganate.
The metal is soluble in solutions of chlorine, bromine, thiosulphates and cyanides; and also in solutions which generate chlorine, such as mixtures of hydrochloric acid with nitric acid, chromic acid, antimonious acid, peroxides and nitrates, and of nitric acid with a chloride.
Skey showed that in substances which contain small quantities of gold the precious metal may be removed by the solvent action of iodine or bromine in water.
It oxidizes rapidly when exposed to air, and burns when heated in air, oxygen, chlorine, bromine or sulphur vapour.