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Journal of the Chemical Society, Ediciķ 1,Pāgines 1-776
Chemical Society (Great Britain)
Visualitzaciķ de fragments - 1969
acetic acid action active added alcohol alkali ammonia amount angle anhydride aniline appears atoms axial axis base benzene boiling bromide calculated carbon cent chemical chloride cold colouring compound concentrated considerable constant containing cooling corresponding crystallised crystals derivative described determined dilute direction dissolved distilled double effect ether ethylic evidence examination excess experiments fact flame formation formed formula further gave given gives grams heated Hofmann hydrogen hydrogen bromide increase indices interesting latter lead lead dioxide light liquid means median melting metal method mixture molecular molecule nature nitrate observed obtained optical oxide position potash potassium precipitate prepared present prisms pure quantity readily reduced refraction requires respectively rotation rubidium salt separated shown silver similar sodium soluble solution specific substance sulphate sulphuric temperature tion tube values volume weight whilst yield
Pāgina 593 - Now if we take 20 equivalents of carbon, 11 equivalents of hydrogen, 1 equivalent of nitrogen, and 2 equivalents of oxygen, as the composition of quinine, it will be obvious that naphthalidine, differing only by the elements of two equivalents of water, might pass into the former alkaloid simply by an assumption of water. We cannot, of course, expect to induce the water to enter merely by placing it in contact, but a happy experiment may attain this end by the discovery of an appropriate metamorphic...
Pāgina 628 - The most superficial glance at the present condition of European states shows, that those which linger in the race cannot hope to escape the partial diminution and perhaps the final annihilation of their resources. It is with nations as with nature, which, according to a happy expression of Goethe, knows no pause in ever-increasing movement, development, and production — a curse still cleaving to standing still.
Pāgina 596 - ... than coal-tar naphtha may be used in which the brown substance is soluble and the colouring matter is not soluble. I then free the residue from the naphtha by evaporation, and digest it with methylated spirit, or any other liquid in which the colouring matter is soluble, which dissolves out the new colouring matter. I then separate the methylated spirit from the colouring matter by distillation, at a temperature of 100° C. or 212° F.
Pāgina 663 - ... hydrogen, the power of combining with acids has altogether disappeared. In these hydrogen-compounds the gradation of properties is. indeed even more marked than in their trimethylated and triethylated derivatives. On comparing the terminal points of the series, ammonia and antimonietted hydrogen, we cannot fail to be struck by the dissimilarity of properties which at the first glance appears to limit the analogy of the two compounds to a mere parallelism of composition. In the methylated and...
Pāgina 596 - At this time neither I nor my friends had seen the inside of a chemical works, and whatever knowledge I had was obtained from books. This, however, was not so serious a drawback as at first it might appear to be, as the kind of apparatus required, and the character of the operations to be performed, were so entirely different from any in use that there was but little to copy from.
Pāgina 597 - ... had it not been for this discovery, the coal-tar colour industry could not have been started.
Pāgina 595 - Although the results were not so encouraging as could be wished, I was persuaded of the importance of the colouring matter, and the result was that, in October, I sought an interview with my old master Hofmann and told him of the discovery of this dye, showing him patterns dyed with it, at the same time saying that as I was going to undertake its manufacture, I was sorry that I should have to leave the Royal College of Chemistry. At this he appeared annoyed, and spoke in a very discouraging manner,...
Pāgina 217 - The flames of cyanogen and acetylene are peculiar in respect that the te'mperature of individual decomposing molecules is not dependent entirely on the temperature generated by the combustion which is a function of the tension of dissociation of the oxidised products, carbonic acid and water. We have no means of defining with any accuracy the temperature which the particles of such a flame may reach. We know, however, that the mean temperature of the flames of carbonic oxide and hydrogen lies between...
Pāgina 834 - ... of air comparatively cold. The real temperature of visible flame is perhaps as high as any we are acquainted with. Mr. TENNANT was in the habit of showing an experiment, which demonstrates the intensity of its heat. He used to fuse a small filament of platinum in the flame of a common candle; and it is proved by many facts, that a stream of air may be made to render a metallic body white hot, yet not be itself luminous.