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hydrogen, the chemistry and manufacture of

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THE IHEMISTRY AND MANUFACTURE OF HTDROGEN BY P. LlTHERLAND TEED \R is MjMlNINC* AND METALLURGY), A I M M MAJOR, KAI-, LONDQ. EDWARD 1 1919 [...]... atmospheres the flame is strongly luminous T h e combination of oxygen and h y d r o g e n is most violent if the t w o gases are present in t h e relative quantities given in t h e equation, viz two volumes of hydrogen a n d one of oxygen If one or other of the gases is in excess of these quantities the violence of the reaction is reduced a n d the quantity of the gas in excess of that required by the equation... exceptions to the rule being capable of explanation on the basis of undoubted secondary reactions O n the basis of this relationship between the velocity of sound in t h e burning gases and the velocity of explosion, Professor H B Dixon calculated the velocity of the explosion wave in certain gaseous mixtures and also determined it experimentally, with the results given below:— Velocity of Explosion... to the fact t h a t the speed of burning in oxygen is g r e a t e r t h a n in air, because of the absence of a n y dilution, a n d also because the nitrogen a n d other inert constituents in the air a r e themselves heated at the expense of the flame t e m p e r a t u r e 1 T h e calculated value for the flame t e m p e r a t u r e of h y d r o g e n b u r n i n g in air, assuming that the heat of. .. nature of the gases discharged from volcanoes has been most carefully studied from about the middle of the last century, with the result that the chemical composition of the gas discharged has been determined at many different volcanoes, and a t different times at the same volcano F r o m these investigations it would appear that in the more violent discharges there are very considerable amounts of hydrogen,. .. enormously in excess of the other a condition may arise in which the dilution is so great that on sparking the mixture n o reaction takes place 1 Mixtures of air a n d hydrogen in which the air is under 20 per cent (i.e u n d e r 4 per cent, of oxygen) of the total volume b e h a v e in this way T h i s point is of importance in airships, as, providing the purity of t h e h y d r o g e n in the envelope is... react, with the production of w a t e r in m i n u t e q u a n tities In the experiment b y which Professor B a k e r m a d e this discovery h e placed a m i x t u r e of these two gases in a state of great purity b u t not of absolute d r y n e s s (in the ratio of two volumes of h y d r o g e n a n d one of oxygen) in a h a r d glass t u b e closed a t o n e end a n d sealed at the other b y mercury... Reactions of H y d r o g e n w i t h O x y g e n in the Com* bined State* S o far the reaction of h y d r o g e n and oxygen has only been considered when b o t h are in the gaseous form However, such is the attraction of hydrogen for oxygen that w h e n the latter is in combination with some other element the h y d r o g e n will generally combine with the oxygen, forming water and leaving the substance... in the envelope will not cause a n explosion, b u t if t h e quantity of hydrogen by volume falls below this a m o u n t there is a risk of explosion ; h e n c e the procedure of deflating airships when t h e purity has dropped to 80 p e r cent, hydrogen by volume T h e Temperature of Ignition of H y d r o g e n and O x y g e n , — W h e n the two gases are mixed in the proportion of two volumes of. .. takes place, that is to say, t h e w a t e r is decomposed into hydrogen and oxygen, t h e hydrfigen being liberated on the surface of t h e metal t r a y containing the binoxide of tin, and the oxygen a t t h e other pole T h e nascent hydrogen liberated in the neighbourhood of the white tin oxide reduces it on t h e surface of the particle to metallic tin, in accordance w i t h t h e following equation... t b y sunlight H o w e v e r , if the two ^ases are heated, they will combine, b u t their combination is a t t e n d e d with t h e evolution of less heat t h a n 24 HYDROGEN in the case of chlorine T h o m s e n states that the combination of i g r a m m e of hydrogen with 80 grammes of bromine (liquid) is a t t e n d e d with the evolution of 8440 gramme-calories of heat W i t h I o d i n e , — H . if the two gases are present in the relative quantities given in the equation, viz. two volumes of hydrogen and one of oxygen. If one or other of the gases is in excess of these quantities the. Temperature of Ignition of Hydrogen and Oxygen,—When the two gases are mixed in the pro- portion of two volumes of hydrogen and one volume of oxygen it has been found that the temperature of the mixed. the violence of the reaction is reduced and the quantity of the gas in excess of that required by the equation remains as a residue. When one gas is enormously in excess of the other a condition

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