scholarly journals Freezing point Curve for Water Containing Hydrochloric Acid and Phenol

1900 ◽  
Vol 4 (2) ◽  
pp. 130-134
Author(s):  
J. A. Emery ◽  
F. K. Cameron
1921 ◽  
Vol 25 (6) ◽  
pp. 491-494 ◽  
Author(s):  
F. H. Rhodes ◽  
F. E. Hance

1954 ◽  
Vol 32 (5) ◽  
pp. 550-556 ◽  
Author(s):  
Paul A. Giguère ◽  
E. A. Secco

The cooling curves of a number of solutions of deuterium peroxide in heavy water in the concentration range 11% to 95% were measured in order to determine the solid-liquid phase diagram for that binary system. The apparatus of Herington and Handley, which uses a pulsing pressure for stirring the solutions, and a thermistor, was found to be particularly suitable for that purpose. As could be expected the freezing-point curve of the deuterated compounds is closely similar to that of the hydrogen compounds, being shifted up only by about 4° for water-rich solutions and by 2° for peroxide-rich solutions. The melting point of the addition compound, D2O.2D2O very nearly coincides with one of the eutectic points at 46.2% D2O2 and −51.5 °C.; the other eutectic point is at 60.5% D2O2 and −55.1 °C. By extrapolation the melting point of pure deuterium peroxide is found to be 1.5 °C. as compared with −0.43 °C. for hydrogen peroxide. Concentrated solutions of deuterium peroxide exhibit an extreme tendency to supercool, resulting sometimes in formation of glasses even at liquid-air temperature. The previous results of Foley and Giguère for the system H2O–H2O2 were confirmed, specially as regards the melting point of the addition compound H2O2•2H2O.


1901 ◽  
Vol 68 (442-450) ◽  
pp. 171-178 ◽  

In the Third Report of the Alloys Research Committee, published in 1895, Sir W. Roberts-Austen gives an appendix, by Dr. Stansfield, containing an extremely interesting series of cooling curves of the copper-tin alloys. These curves made it evident that for many percentage compositions there were three or even four halts in the cooling due-to separate evolutions of heat, and that some of these changes must have occurred when the metal was solid. A freezing-point curve was also deduced from the cooling curves. The report contained interesting remarks on the meaning of the curves, but a satisfactory explanation was not at that time possible. In June, 1895, Professor H. Le Chatelier also published a freezing-point curve, giving the upper points only. These two curves agree in locating a singular point near the composition Cu 4 Sn, but do not give any singular point nearer to the copper end of the curve.


1903 ◽  
Vol 71 (467-476) ◽  
pp. 409-412 ◽  

This paper is an attempt to fill a very serious gap in the study of alloys. As a rule, an alloy begins to be interesting when the temperature of the liquid alloy has fallen to its freezing point. This point, which records the moment when solid first appears in the liquid, is easily observed on account of the evolution of latent heat that occurs on the formation of solid, and if the freezing points of all the alloys of a series are determined, we can plot the freezing-point curve. Many such curves have been traced in the last ten years: that of the copper-tin alloys is given by the upper line in our diagram. The curve consists of several branches cutting each other in angular points. The one thing that these curves record without ambiguity is the number of different solids that can crystallise out of the liquid alloys, for each branch corresponds to the crystallisation of a different substance. But this is almost all that such curves tell us with certainty. They do not tell us whether the solids forming are the pure metals, or pure compounds, or crystalline solid solutions of the metals. Other experiments are needed to decide such questions.


The following paper is a continuation of two previous papers in which the melting- and freezing-point curves for two pairs of substances, each of which forms mixed crystals, have already been determined. In the first of these papers mixtures of naphthalene and β -naphthol were examined and found to a form a continuous series of mixed crystals and to give curves of Roozeboom's Type I, in which the melting and freezing points of all mixtures lie between the melting points of the pure substances.


The behaviour of mixtures of naphthalene and β-naphthol has already been investigated, and the freezing and melting point curves and the curve of spontaneous crystallisation for these mixtures described.* These substances were found to form a continuous series of mixed crystals, on a curve of Roozeboom’s Type 1, the melting and freezing points of all the mixtures lying between the melting points of the pure substances. The behaviour of mixtures of monochloracetic acid and naphthalene was also investigated, for it was stated by Cady that these substances form mixed crystals of Roozeboom’s Type 5, whose melting and freezing point curves exhibit a minimum or eutectic freezing point. Experiments were therefore made with these substances with the object of determining the form of the curve of spontaneous crystallisation, or supersolubility curve, for mixtures of this type. No sign of the formation of any mixed crystals was observed, however, in a lengthy series of experiments, and it was shown that naphthalene and monochloracetic acid give the ordinary V-shaped freezing point curve for the solutions of two substances in each other, similar to that already obtained for mixtures of salol and betol,§ the only new feature being introduced by the existence of three modifications of monochloracetic acid. The monochloracetic acid and naphthalene mixtures having thus failed as an example of mixed crystals possessing a minimum or eutectic freezing point, another attempt was made to obtain a pair of substances with convenient melting points which form mixed crystals and possess the melting and freezing point curves with minimum eutectic point characteristic of Roozeboom’s Type 5.


This paper is a study of the binary alloys composed of gold and aluminium. The fact that metals in many cases form definite chemical compounds with each other, is becoming increasingly evident as attention is given to the subject. But there are many pairs of metals whose freezing point-curve affords no indication of chemical combination, and which probably do not combine with each other under the conditions of our experiments. It is therefore desirable, in seeking for such compounds, to select a pair of metals which are known to have a peculiar relation to each other. We chose gold and aluminium for several reasons. First, on account of the beautiful purple compound of Sir W. Roberts-Austen, and on account of our own experiments (‘Journal Chemical Society/ vol. 74, 1894), which showed it to be a very stable body in solution. There was also the important point that the alloys of gold and aluminium admit of fairly rapid analysis by the determination of the gold. In the present paper the freezing point method is combined with a microscopic study of the alloys, and we hope that it will be found that the interpretation of the results is more conclusive than in previous papers of our own and of others in which only the one method or the other was employed.


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