Rousseau's view on language Essay Example | Topics and Well Written Essays - 250 words

Rousseau's view on language - Essay Example This means that at first the worlds did not have meaning per se and acquired stable meaning only later in history when speech lost its original characteristics. Furthermore, Rousseau suggests that the theories which argue that the origin of language might be easily explained by the necessity of the people to communicate about future actions and coordinate them are mistaken. He points out the fact that when a person is crying, the situation is understandable without any words as the person feels compassion and might comfort the other person without even knowing the language. As has been mentioned before, one would make no mistake pointing out that speech and song originate for a common source: the desire to convey inner feelings. While they were developing together, there are several factors that accelerated evolution of the former, such as the invention of writing. Indeed, people started to record what they say much earlier than they invented ways to record

News Article Analysis Essay Example | Topics and Well Written Essays - 750 words - 1

News Article Analysis - Essay Example According to Miller, the higher pricing trend is fairly pinpointing the lack of competition in the market. The limited supply from few and rising demand from many locals and international investors is creating lack of competition here. Some suppliers are enjoying the high profits by selling the condominiums in high prices and are intended to cover losses made due to the recession. This concept is derived form the theory of demand-pull price hike. Since the market was showing intensified demand for the condos, the towers also being transformed into condos. It is also creating hype among the potential buyers as constantly rising prices are creating urgency to conduct a deal. This strategy resulted in sales increase according to the letter to attorney journal from the condos developer on Oct. 24, 2012. The market concept tells that less supply and more demand increases the prices in the market and so alike pre-crises market the sellers charging premium prices from customers. Throughout the articles it is reflected that every real state seller especially in the condos is charging high prices taking advantage of the lack of competition in the market. The scarcity of supply shaped some sort of oligopolistic competition in the Manhattan market. ... The shortage of supply in the market is resulted due to recession because of which the construction was brought at halt.. The recession in the US economy affected all the business sectors throughout the country. Every state of US faced a recession’s impact. The system’s problem originated when the lending capacity of banks became weaker because of the bankruptcies of huge multinationals and more specifically banks. The bankruptcy of huge firms and investment house Lehman Brothers played the role of nail in the coffin and was the actual reason for bringing the recession in the US economy.. The mortgage lenders analyzed the situation and stopped making more investments on real state industry. Also, the investors of real state industry delayed their plans of investment because of the decreasing demand. The real state investors in Manhattan moved with trend and decreased their investments in the real sate sector of the state. Those projects that were under construction at t he time of recession were the only supply for near future. Also, real real-estate constructors bought the drowning investors’ unit at bucks in recession. Hence, when the economy started getting recover after the phase of recession there were only few suppliers of newly constructed condominiums were competing in the market. Also, for the period of next two years they were the only suppliers in the market. The recovery led the people of Manhattan to bring back their investments in purchasing condominiums which increased demand. Real estate companies increased prices because of lack of competition or the unavailability of demanded supply. The prices were charged higher with a margin of good percentage and due

What Are The Concepts Of Thermochemistry Environmental Sciences Essay

What Are The Concepts Of Thermochemistry Environmental Sciences Essay The beginnings of modern thermochemistry, though made independently of the doctrine of the conservation of energy, are practically contemporaneous with the recognition of that law, and without it the science could scarcely have reached the degree of development which it rapidly attained. Thomas Andrew and, especially Hess were the first who systematically investigated thermochemical effects in solution, and arrived at conclusions from their experimental data which still possess validity. Andrews, for example, found that when a series of acids were under similar conditions used to neutralize a given amount of a base, the quantity of heat evolved on the neutralization was the same in all cases. Hess, from his work, arrived at the converse conclusion, that when a series of bases were used to neutralize a given amount of an acid, the heat of neutralization was always the same. Both of these statements are correct when the powerful mineral acid and bases are considered, exceptions only ar ising when weak acids and bases are employed. Again, Andrews discovered that when one metal displaces another from solution of its salts (e.g. zinc with solutions of copper salts), the thermal effect is practically independent of the nature of the acid radical in the salt employed. Andrews likewise found that when the heat evolved on. the displacement from its salts of a metal M by a metal M is added to the heat of displacement of another metal M by M, the sum is equal to the heat which is evolved on the direct displacement of M from its salts by M. This affords an example of a principle which had been stated by Hess in a very general form under the name of the Law of Constant Heat Sums namely, that the thermal effect of a given chemical action is the same, independently of the character and number of the stages in which it takes place. Thus, in the above example, it is immaterial whether M displaces M from its salt directly, or whether M first displaces M, which is then used to di splace M. This important principle is a direct consequence of the law of the conservation of energy, but was discovered independently by Hess from accurate experiment. Oxidation of Zn to ZnO . . 5291 units à ¢Ã¢â€š ¬Ã… ¾ S to SO 3 . 6384 à ¢Ã¢â€š ¬Ã… ¾ Dissolution of SO 3 in much water. .. . . 2566 à ¢Ã¢â€š ¬Ã… ¾ ZnO in the resulting aqueous H2S04. 1609 à ¢Ã¢â€š ¬Ã… ¾ 1585 o à ¢Ã¢â€š ¬Ã… ¾ Deduct heat of dissolution of anhydrous ZnSO 4 . . 11 93 à ¢Ã¢â€š ¬Ã… ¾ Heat of formation of ZnSO 4 from Zn, S, and 40 = 14657 à ¢Ã¢â€š ¬Ã… ¾ Hess employed this principle to determine indirectly the heat of formation of compounds from their elements, when this magnitude, as is generally the case, was inaccessible to direct measurement. Thus the heat of formation of anhydrous zinc sulphate, ZnSO 4j which cannot be determined directly, may be arrived at by summation (in Hesss units) as follows: Heats of formation are still determined for the most part in a precisely similar manner. Hess also stated another principle on empirical grounds, which, although admitting of many exceptions, is of considerable utility and significance. It had been known long before his time that when solutions of neutral salts were mixed, and no precipitate resulted, the mixed solution was also neutral. Hess now observed that in the process of mixing such neutral solutions no thermal effect was produced that is, neutral salts in aqueous solution could apparently interchange their radicals without evolution or absorption of heat. These experimental results were generalized by him under the title of the Law of Thermoneutrality. After the investigations of Hess and Andrews, a great deal of excellent experimental work was performed by P. A. Favre and J. T. Silbermann, whose chief theoretical achievement was the recognition that the heat of neutralization of acids and bases was additively composed of two constants, one determined by the acid and the other by the base. This dedction harmoniz ed the observations of Andrews and of Hess previously alluded to, and also accounted satisfactorily for the Law of Thermoneutrality. Julius Thomson was the first investigator who deliberately adopted the principle of the conservation of energy as the basis of a thermochemical system. His thermochemical work was begun in 1853, but most of his experiments were performed in the years 1869-82, the whole being published collectively, under the title Thermochemische Untersuchungen, in four volumes. Somewhat later than Thomson, Marcellin P. E. Berthelot began (in 1873) a long series of thermochemical determinations. It is to these two investigators and their pupils that most of our exact thermochemical data are due. Thomsen and Berthelot independently enunciated a generalization (commonly known as Berthelots Third Principle, or Principle of Maximum Work), which may be stated in brief as follows: Every pure chemical reaction is accompanied by evolution of heat. Whilst this principle is undoubtedly applicable to the great majority of chemical actions under ordinary conditions, it is subject to numerous exceptions, and cannot therefore be taken (as its authors originally intended) as a secure basis for theoretical reasoning on the connexion between thermal effect and chemical affinity HEAT IN THERMOCHEMISTRY . The existence of reactions which are reversible on slight alteration of conditions at once invalidates the principle, for if the action proceeding in one direction evolves heat, it must absorb heat when proceeding in the reverse direction. As the principle was abandoned even by its authors, it is now only of historical importance, although for many years it exerted considerable influence on thermochemical research. 2. From the standpoint of the law of conservation of energy, the relation between chemical and thermochemical action bears the following aspect: A given amount of any substance under given conditions possesses a perfectly definite amount of intrinsic energy, and, no matter what chemical and physical transformations the substance may undergo, it will, when it returns to its original state, possess the original amount of intrinsic energy. If we consider now the transformation of one system of chemical substances into another system under specified conditions, we shall find that in general the intrinsic energy of the second system is different from the intrinsic energy of the first. Let us assume, as is commonly the case, that the intrinsic energy of the initial system is greater than that of the final system. When the first system then is transformed into the second, the excess of energy which the former possesses must appear in the shape of heat, light, electrical energy, mechanical energy, c. It is for the most part a simple matter to obtain the excess of energy entirely in the form of heat, the amount of which is easily susceptible of measurement, and thus the existence of thermochemistry as a practical science is rendered possible. Since the intrinsic energies of the two systems under given conditions are invariable, the difference between them is constant, so that the heat evolved when the first system is converted into the second is equal to that absorbed when the second system is re-transformed into the first (cf. Lavoisier and Laplace, ante, 1). The total thermal effect, too, which is associated with the transformation, must be the same, whether the transformation is conducted directly or indirectly (Hesss Law of Constant Heat Sums), since the thermal effect depends only on the intrinsic energies of the initial and final systems. Since the intrinsic energy of a substance varies with the conditions under which the substance exists, it is necessary, before proceeding to the practical application of any of the laws mentioned above, accurately to specify the conditions of the initial and final systems, or at least to secure that they shall not vary in the operations considered. It is also a necessary condition for the application of the preceding laws that no form of energy except heat and the intrinsic energy of the substances should be ultimately involved. For example, when metallic zinc is dissolved in dilute sulphuric acid with production of zinc sulphate (in solution) and hydrogen gas, a definite quantity of heat is produced for a given amount of zinc dissolved, provided that the excess of energy in the initial system appears entirely as heat. This provision may not always be fulfilled, since by placing the zinc in electrical contact with a piece of platinum, likewise immersed in the sulphuric acid, we can g enerate a current of electricity through the solution and the metallic part of the circuit. The reaction as before is completely expressed by the chemical equation Zn+H2S04 =ZnSO 4 H+ 2, the initial and final systems being exactly the same as in the first case; yet the amount of heat generated by the action is much smaller, a quantity of the intrinsic energy having been converted into electrical energy. This electrical energy, however, is equivalent to the heat which has disappeared, for it has been shown experimentally that if it is converted into heat and added to the heat actually evolved, the total quantity of heat obtained is exactly equal to that produced by the direct dissolution of the zinc in the absence of platinum. 3. The following conditions have to be considered as affecting in a greater or less degree the intrinsic energy of the initial and final systems: (1) Dilution of solutions. (2) Physical state. (3) Change of volume. (4) Allotropic modifications. (5) Temperature. (i) Generally speaking, there is a considerable thermal effect when a substance is dissolved in water, and this effect varies in magnitude according to the amount of water employed. It is only, however, when we deal with comparatively concentrated solutions that the heat-effect of diluting the solutions is at all great, the heat-change on diluting an already dilute solution being for most practical purposes negligible. In dealing, therefore, with dilute solutions, it is only necessary to state that the solutions are dilute, the exact degree of dilution being unimportant. It occasionally happens that a change in dilution affects the chemical action that occurs. Thus if concentrated instead of dilute sulphuric acid acts upon zinc, the action takes place to a great extent not according to the equation given above, but according to the equation Zn +2H 2 SO 4 = ZnS04+S02+2 H20, sulphur dioxide and water being produced instead of hydrogen. Here we have a different final system with a diffe rent amount of intrinsic energy, so that the thermal effect of the action is altogether different. (2) The physical state of the reacting substances must be considered, since comparatively large amounts of heat are absorbed on fusion and on vaporization . Thus the heat of fusion of ice(for H 2 O=18 g) is 1440 cal., and the heat of vaporization of water at 100 °, for the same quantity, 9670 cal. (3) The effect of change of volume against external pressure (due to production or consumpion of mechanical energy) may be neglected in the case of solids, liquids or solutions, but must usually be taken into account when gases are dealt with. Each grammemolecule of a gas which appears under constant pressure during a chemical action (e.g. hydrogen during the action of zinc on dilute sulphuric acid) performs work equivalent to 580 cal. at the ordinary temperature, which must be allowed for in the thermochemical calculation. A similar correction, of opposite sign, must be made when a gramme-molecule of gas disappears during the chemical action. (4) When a substance e.g. carbon, phosphorus , sulphur exists in allotropic forms, the particular variety employed should always be stated, as the conversion of one modification into another is frequently attended by a considerable thermal effect. Thus the conversion of yellow into red phosphorus evolves about one-sixth of the heat of combustion of the latter in oxygen, and so the knowledge of which variety of phosphorus has been employed is of essential importance in the thermochemistry of that element. (5) The influence of temperature on the thermal effect of a chemical action is sometimes considerable, but. since the initial and final temperatures, which alone determine the variation in the thermal effect, are in almost all cases within the ordinary laboratory range of a few degrees, this influence may in general be neglected without serious error. 4. Methods. In order to estimate the thermal effect of any chemical process, use is made of the ordinary methods of calorimetry, the particular method being selected according to the nature of the chemical action involved. In almost every case the method of mixture (see Calomitry) is employed, the method of fusion with Bunsens ice-calorimeter being only used in special and rarely occurring circumstances. As a very great number of important chemical actions take place on mixing solutions, the method for such cases has been thoroughly studied. When the solutions employed are dilute, no water is placed in the calorimeter, the temperature-change of the solutions themselves being used to estimate the thermal effect brought about by mixing them. Known quantities of the solutions are taken, and the temperature of each is accurately measured before mixing, the solutions having been allowed as far as possible to adjust themselves to the same temperature. The change of temperature of the solutions after the mixing has taken place is then observed with the usual precautions. It is of course in such a case necessary to know the specific heat of the liquid in the calorimeter. Thomsen by direct experiment found that the heat-capacity of a dilute aqueous solution diverged in general less than i per cent. from the heat-capacity of the water contained in it, the divergence being sometimes in one sens e, sometimes in the other. He therefore abstained from determining for each case the specific heats of the solutions he employed, and contented himself with the above approximation. Berthelot, on the other hand, assumed that the heat-capacity of an aqueous solution is equal to that of an equal volume of water, and calculated his results on this assumption, which involves much the same uncertainty as that of Thomsen. Since thermochemical measurements of this type may be frequently performed with an error due to other causes of much less than i per cent., the error introduced by either of these assumptions is the chief cause of uncertainty in the method. The calorimeter used for solutions is usually cylindrical, and made of glass or a metal which is not, attacked by the reacting substances. The total quantity of liquid employed need not in general exceed half a litre if a sufficiently delicate thermometer is available. The same type of calorimeter is used in determining the heat of solution of a solid or liquid in water. Combustion calorimeters are employed for observing the heat generated by the brisk interaction of substances, one of which at least is gaseous. They are of two kinds. In the older type the combustion chamber (of metal or glass) is sunk in the calorimeter proper, tubes being provided for the entrance and exit of the gaseous substances involved in the action. These tubes are generally in the form of immersed in the water of the calorimeter. In the newer type (which was first proposed by Andrews for the combustion of gases) the chemical action takes place in a completely closed combustion chamber of sufficient strength to resist the pressure generated by the sudden action, which is often of explosive violence. The steel combustion chamber is of about 250 c.c. capacity, and is wholly immersed in the calorimeter. To withstand the chemical action of the gases, the calorimetric bomb is lined either with platinum, as in Berthelots apparatus, or with porcelation, as in Mahlers. For ordinary combustions compressed oxygen is used, so that the combustible substance burns almost instantaneously, the action being induced by means of some electrical device which can be controlled from without the calorimeter. The accuracy of heats of combustion determined in the closed calorimeter is in favourable cases about one-half per cent. of the quantity estimated. 5. Units and Notation in thermochemistry The heat-units employed in thermochemistry have varied from time to time. The following are those which have been in most general use: Small calorie or gramme calorie. cal. Large or kilogramme calorie. Cal. Centuple or rational calorie. K. The centuple calorie is the amount of heat required to raise 1 g. of water from o ° C. to C., and is approximately equal to ioo cal. The large calorie is equal to 1000 cal. In view of the not very great accuracy of thermochemical measurements, the precise definition of the heat-unit employed is not a matter of special importance. It has been proposed to adopt the joule, with the symbol j, as thermochemical unit for small quantities of heat, large amounts being expressed in terms of the kilojoule, Kj =100o j. (For the exact relation between these heat-units, see Calorimetry.) For ordinary thermochemical work we may adopt the relation 1 cal. = 4.18 j, or 1 Cal. = 4.18 Kj. Except for technological purposes, thermochemical data are not referred to unit quantity of matter, but to chemical quantities i.e. to the gramme-equivalents or gramme-molecules of the reacting substances, or to some multiples of them. The notation which Julius Thomsen employed to express his thermochemical measurements is still extensively used, and is as follows: The chemical symbols of the reacting substances are written in juxtaposition and separated by commas; the whole is then enclosed in brackets and connected by the sign of equality to the number expressing the thermal effect of the action. The chemical symbols stand for quantities measured in grammes, and heat-evolution is reckoned as positive, heat-absorption as negative. Thus [S, 20] =71100 cal. indicates that 71100 calories are evolved when 32 grammes of sulphur react with 2 X 16 grammes of free oxygen to form sulphur dioxide. It is of course necessary in accurate work to state the conditions of the reaction. In the above instance the sulphur is supposed to be in the solid rhombic modification, the oxygen and sulphur dioxide being in the gaseous state, and the initial and final systems being at the ordinary temperature. Again, the equation [2N, 0] =-18500 cal. indicates that if 28 grammes of nitrogen could be made to unite directly with 16 grammes of oxygen to form nitrous oxide, the union would cause the absorption of 18500 calories. When substances in solution are dealt with, Thomsen indicates their state by affixing Aq to their symbols. Thus [NaOH Aq, HNO 3 Aq] =13680 cal. represents the heat of neutralization of one gramme-equivalent of caustic soda with nitric acid, each in dilute aqueous solution before being brought into contact. One draw back of Thomsens notation is that the nature of the final system is not indicated, although this defect in general causes no ambiguity. Berthelots notation defines both initial and final systems by giving the chemical equation for the reaction considered, the thermal effect being appended, and the state of the various substances being affixed to their formulae after brackets. W. Ostwald has proposed a modification of Berthelots method which has many advantages, and is now commonly in use. Like Berthelot, he writes the chemical equation of the reaction, but in addition he considers the chemical formula of each substance to express not only its material composition, but also the (unknown) value of its intrinsic energy. To the right-hand member of the equation he then adds the number expressing the thermal effect of the reaction, heat-evolution being as before counted positive, and heat-absorption negative. The mass-equation then becomes an energy-equation. He thus writes S+02=S02+7110o cal., which expresses the fact that the intrinsic energy of the quantities of sulphur and oxygen considered exceeds that of the sulphur dioxide derived from them by 71100 cal. when thermal units are employed. The equation H2+12=2HI-12200 cal. expresses that under certain conditions the intrinsic energy of hydriodic acid is greater than the intrinsic energy of its component elements by 12200 cal., i.e. that hydriodic acid is formed from its elements with absorption of this amount of heat. Energyequations, such as the above, may be operated with precisely as if they were algebraic equations, a property which is of great advantage in calculation. Thus by transposition we may write the last equation as follows 2HI =H2+12+12200 cal., and thus express that hydriodic acid when decomposed into its elements evolves 12200 cal. for the quantity indicated by the equation. Ostwald has made the further proposal that the formulae of solids should be printed in heavy type (or within square brackets), of liquids (solutions, c.) in ordinary type, and of gases in italics (or within curved brackets), so that the physical state the substances might be indicated by the equation itself. Thus the equation Cl 2 -1-2KI, Aq=2KC1, Aq+12+52400 cal., or (C12) +2KI, Aq =2KC1, Aq+[12]-I-52400 cal., would express that when gaseous chlorine acts on a solution of potassium iodide, with separation of solid iodine, 52400 calories are evolved. 6. Heat of Formation. For thermochemical calculations it is of great importance to know the heat of formation of compounds from their elements, even when the combination cannot be brought about directly. As an example of the use of Ostwalds energy-equations for the indirect determination we may take the case of carbon monoxide. The following equations give the result of direct experiment  :- C +20 = CO 2+943 oo cal. CO+ O=CO 2 +68000 cal. If now it is required to find the heat of formation of the compound CO, which cannot be directly ascertained, we have merely to subtract the second equation from the first, each symbol representing constant intrinsic energy, and thus we obtain C+0 00= 26300 cal., or C+0=C0+26300 cal., that is, the heat of formation of a gramme-molecule of carbon monoxide is 26300 cal. As has already been stated, the heat of formation of a compound is the amount (expressed in thermal units) by which its intrinsic energy exceeds or falls short of that of the elements which enter into its composition. Now of the absolute values of intrinsic energy we know nothing; we can only estimate differences of intrinsic energy when one system is compared with another into which it may be directly or indirectly converted. But since the elements cannot be converted one into the other, we are absolutely without knowledge of the relative values of their intrinsic energy. This being the case, we are at liberty to make the assumption that the intrinsic energy of each element (under specified conditions) is zero, without thereby introducing any risk of self-contradiction in thermochemical calculations. This assumption has the great advantage, that the intrinsic energy of a compound relatively to its elements now appears as the heat of formation of the compound with its sign reversed. Thus if we consider the energyequation C +02 = CO 2+943 00 cal., and replace the symbols by the values of the intrinsic energy, viz. zero for carbon and oxygen, and x for carbon dioxide, we obtain the equation o+o=x+94300 cal. or x = 94300 cal. With knowledge then of the heats of formation of the substances involved in any chemical action, we can at once calculate the thermal effect of the action, by placing for each compound in the energy-equation its heat of formation with the sign reversed, i.e. its heat of decomposition into its elements. Thus if we wish to ascertain the thermal effect of the action Mg+CaO =MgO+Ca, we may write, knowing the heats of formation of CaO and Mg0 to be 131000 and 146000 respectively, 0-131000 = 0-146000+x x =15000 cal. Since heats of formation afford such convenient data for calculation on the above method, they have been ascertained for as many compounds as possible. Substances with positive heats of formation are termed exothermic; those with negative heats of formation are termed endothermic. The latter, which are not very numerous, give out heat on decomposition into their elements, and are more or less unstable. Amongst endothermic compounds may be noted hydriodic acid, HI, acetylene, C 2 H 2, nitrous oxide, N 2 O, nitric oxide, NO, azoimide, N 3 H, nitrogen trichloride, NC1 3. Some of these pass into their elements with explosive violence, owing to the heat generated by their decomposition and the gaseous nature of the products. 7. Heat of Combustion The thermochemical magnitude which is universally determined for organic compounds is the heat of combustion, usually by means of the calorimetric bomb. The relation between the heat of combustion of a hydrocarbon and its heat of formation may be readily seen from the following example. The hydrocarbon methane, CH 4, when completely burned to carbon dioxide and water, generates 213800 cal. We may therefore write CH 4 +40 = C02+2H20+213800. Now we know the heats of formation of carbon dioxide (from diamond) and of liquid water to be 94300 cal. and 68300 cal. respectively. The above equation may consequently be written, if x is the heat of formation of methane, -x+0 = -94300-(2 X 68300) +213800 x =17000 cal. This heat of formation, like that of most hydrocarbons, is comparatively small: the heat of formation of saturated hydrocarbons is always positive, but the heat of formation of unsaturated hydrocarbons is frequently negative. or example, ethylene, C2H4 j is formed with absorption of 16200 cal., acetylene, C 2 H 2, with absorption of 59100 cal., and liquid benzene, C 6 H 6, with absorption of 9100 cal. Since the heat of combustion of a hydrocarbon is equal to the heat of combustion of the carbon and hydrogen it contains minus its heat of formation, those hydrocarbons with positive heat of formation generate less heat on burning than the elements from which they were formed, whilst those with a negative heat of formation generate more. Thus the heat generated by the combustion of acetylene, C 2 H 2, is 316000 cal., whereas the heat of combustion of the carbon and hydrogen composing it is only 256900 cal., the difference being equal to the negative heat of formation of the acetylene. For substances consisting of carbon, hydrogen and oxygen, a rule was early devised for the purpose of roughly calculating their heat of combustion (J. J. Welters rule). The oxygen contained in the compound was deducted, together with the equivalent amount of hydrogen, and the heat of combustion of the compound was then taken to be equal to the heats of combustion of the elements in the residue. That the rule is not very accurate may be seen from the following example. Cane-sugar has the formula C12H22011. According to Welters rule, we deduct II 0 with the equivalent amount of hydrogen, namely, 22 H, and are left with the residue 12 C, the heat of combustion of which is 1131600 cal. The observed heat of combustion of sugar is, however, 1354000, so that the error of the rule is here 20 per cent. A much better approximation to the heat of combustion of such substances is obtained by deducting the oxygen together with the amount of carbon necessary to form C02, and then ascertaining the amount of heat produced by the residual carbon and hydrogen. In the above case we should deduct with II 0 the equivalent amount of carbon 5.5 C, thus obtaining the residue 6.5 C and 22 H. These when burnt would yield (6.5 X9430o)+(II X68300) =1364250 cal., an amount which is less than 1 per cent. different from the observed heat of combustion of sugar. Neither of the above rules can be applied to carbon compounds containing nitrogen 8. Heat of Neutralization It has already been stated that the heats of neutralization of acids and bases in aqueous solution are additively composed of two terms, one being constant for a given base, the other constant for a given acid. In addition to this, the further regularity has been observed that when the powerful monobasic acids are neutralized by the powerful monacid bases, the heat of neutralization is in all cases the same. The following table gives the heats of neutralization of the commoner strong monobasic acids with soda: Hydrobromic acid Hydriodic acid Nitric acid Chloric acid Bromic acid Within the error of experiment these numbers are identical. It was at one time thought that the greater the heat of neutralization of an acid with a given base, the greater was the strength of the acid. It is now known, however, that when weak acids or bases are used, the heat of neutralization may be either greater or less than the normal value for powerful acids and bases, so that there is no proportionality, or even parallelism, between the strengths of acids and their heats of neutralization . sodium carbonate- Na 2 CO 3.. . Na 2 CO 3, H 2 O . Heat of Solution. +5640 cal. +2250 à ¢Ã¢â€š ¬Ã… ¾ Heat of Hydration. +339 0 cal. Na 2 CO 3, 2H 2 0 . +20 à ¢Ã¢â€š ¬Ã… ¾ +5620 à ¢Ã¢â€š ¬Ã… ¾ Na 2 CO 3, IoH 2 O . 16160 à ¢Ã¢â€š ¬Ã… ¾ +21800 à ¢Ã¢â€š ¬Ã… ¾ II. Sodium sulphate- Na 2 SO 4 +460 cal. Na 2 SO 4, H 2 O . 1900 à ¢Ã¢â€š ¬Ã… ¾ +2360 cal. Na2S04, IoH 2 O . 18760 à ¢Ã¢â€š ¬Ã… ¾ +19200 à ¢Ã¢â€š ¬Ã… ¾ 9. Heat of Solution When substances readily combine with water to form hydrates, the heat of solution in water is usually positive; when, on the other hand, they do not readily form hydrates, or when they are already hydrated, the heat of solution is usually negative. The following examples show the effect of hydration on heat of solution in a large quantity of water: io. Application of the Second Law thermodynamics to Thermochemistry. What is commonly understood by thermochemistry is based entirely on the first law of thermodynamics, but of recent years great progress has been made in the study of chemical equillibrium by the application of the second law. For an account of work in this direction see Chemical action. BIBLIOGRAPHY. Julius Thomsen, Thermochemische Untersuchungen (Leipzig, 1882-86); M. Berthelot, Essai de Mecanique Chimique fondee sur la Thermochimie (Paris, 1879); Thermochimie, donnees et lois numeriques (Paris, 1897); W. Ostwald, Lehrbuch der allgemeinen Chemie, 2nd ed., vol. ii. part I, pp. 1-517 (Leipzig, 1893); M. M. P. Muir and D. M. Wilson, Elements of Thechemistry (London, 1885); P. Duhem, Traite de Mecanique Chimique (Paris, 18 97-99); J. J. van Laar, Lehrbuch der mathematischen Chemie (Leipzig, 1901). (J. WAL.)

Analyzing John Mayer :: essays research papers

Often, lyrics are created for people to relate to them. It is common for many individuals to feel as though they found a â€Å"common ground† with the artist who wrote the lyrics. In John Mayer’s song. â€Å"Split Screen Sadness†, it is very easy to relate to. The music to the song is very influential in setting the mood for the lyrics. Violins and other string instruments add to the sad tone of the song. The theme of this song is that the speaker is explaining how he broke up with his girlfriend (â€Å"And I know well it’s me who called it over...†), but now he regrets it.   Ã‚  Ã‚  Ã‚  Ã‚  The speaker of the lyrics could either be a man or a woman, who is in love with somebody who lives far away from them. Mayer uses colloquial language to set the â€Å"common† tone of the song. John Mayer uses quotes from other songs (â€Å"’All you need is love†¦Ã¢â‚¬â„¢Ã¢â‚¬ ) to express how other songs express how the speaker is feeling. Inside, he wishes that his significant other would have fought for him to not end it and not let him get away. The speaker can not figure out why he isn’t the way he was when deep down inside, he knows it’s because he doesn’t have the person he depended on most.   Ã‚  Ã‚  Ã‚  Ã‚  In the lines, â€Å"I called†¦because†¦I just†¦need to feel you on the line†, the speaker is expressing how he takes comfort in hearing her voice. She was most likely the stability in his life and now he doesn’t have that anymore. The speaker is sick of fighting the feeling of longing he has for her and wishes that they were still together since their love was so strong. Mayer uses the repetition of certain lines to form a general refrain (â€Å"Two wrongs make it all alright tonight†).

Analize a Conflict in “Rip Van Winkle” Essay

One of the main conflicts in the story â€Å"Rip Van Winkle† is about Rip falling asleep for 20 years. To escape the verbal abuse of his wife that he had to deal with every day, Rip left to the forest with his dog Wolf. While he was enjoying a calm view at the top of the mountain, a strange man yelled his name over and over. The man reached Rip’s location and asked him if he could help him with the bags he carried. Rip helped the man and they headed to the mountain torrent. When they got there, they found a group of strange men playing nine-pins. Rip drank some Dutch gin that the men gave him, got really drunk, and fell asleep. When he woke up his dog was missing and his gun had blemished. He decided to go back to his town, but all the routes to get there had changed. He finally got to his town and saw that everything and everyone had changed. Rip even noticed that he had grown a one foot long beard. Nobody recognized him so they thought he was a spy, since he was talking about the king while others were talking about George Washington and the war. A girl approached him and he started asking her who her father and mother were. She said Rip Van Winkle and Dame Van Winkle. Rip figured that was his daughter so he told her that he was her father. She was very happy so see him again and brought him to live with her. Rip’s sleep’s real meaning is that he is escaping from his family and his responsibilities. Irving, the author of the story, had Rip draw in to sleep in the first place, so his character could have an adventure when he woke up, not just so he could escape the present. It’s important to see both points because Rip going into the spiritual woods means both escape and adventure. The point that Irving was making was that slowness will cause you to miss out on the things of the future. This story is like showing us what would happen if we could escape our responsibilities and come back at a convenient time. The fact that Rip’s wife had always nagged on him didn’t make him sorry that he slept for as long as he did. He was actually relieved because he escaped the snatch that his wife had on him. It seemed that she took away a part of his man-hood by always telling him what to do and what not to do. Rip then returned back to the town square and realized what had happened. Not too many people believed his story but reality struck and people started believing him. He was no longer looked at as a lazy irresponsible man, but as a hero. During the Romantic Period of American Literature it was believed that imagination is greater than logic and that imagination is the greater solution to finding truth and beauty, what most authors valued. Romantic writers also believed that cities led to corruption; therefore nature is a safe place to become more spiritual. This is why Rip Van Winkle schemes into the forest with his dog to escape the attack of his wife. Sleeping for 20 years is where the â€Å"imagination is greater than logic† part comes into play. The moral of the story, however, is to have your priorities in order. Rip helped neighbors whenever possible, yet was unwilling towards his family. Of course sleeping for 20 years isn’t reasonable for us. Whether Irving is romantic or not, the point is to display to every reader throughout time that we cannot sleep through a revolution, or shrink our responsibilities.

Racism in the Tuskegee Experiment Essay

The Tuskegee experiment, begun in 1932 by the United States Public Health Service in Macon County, Alabama, used 400 black men who suffered from advanced stages of syphilis.   This study was not a means of finding a cure; the patients offered no preventative measures to prolong or better life.   Although the history and nature of syphilis was well understood, certain scientists believed that more research could certainly be done. In terms of whom to study, the doctors developing the format discovered a â€Å"ready-made situation† (Jones 94). Macon County Alabama was impoverished, like much of the country in 1932.   The selection process began during the depression, a time of separation and intolerance.   In the rural South, where we find Tuskegee, the men chosen were not seen, at the time, as equal in any sense of the word. Jones refers to prominent doctors of the region who, in the late 1800s, scientifically defined diseases that were peculiar to the race.   One such disease, Cachexia Africana, caused the subject to eat dirt.   The public did not question such obviously ridiculous claims at the time.   In fact, the public heralded these doctors and requested a manual for treating blacks in order to save slave-owners and the like money in paying for doctors (17).   Given the distaste for the ethnicity of the subjects, could their ethnicity have been a factor in the selection process? At the time, the medical profession had already made some false assumptions about the African American race in general.   Jones reiterated the white-held theory that black men had larger penises and little constraints when it came to sexual intercourse (23).   It was also believed that they were harder to treat for syphilis because African Americans were stupid. In examining this mindset, it becomes clear why the government erringly felt it should go to the poorer black communities in rural Alabama conduct a syphilis study.   Believed to be an immoral sex-centered culture placed at the level of animals, the government would put them in league with mice and rats.   As disgusting as the premise is, the doctors needed lab animals and set out to find them. If this were true – how could the government get away with it?   Blatant disregard for humanity and life could not go unnoticed.   However, the geographical area in question had just been the last state of the union to discontinue chain gang use in its penitentiaries in 1928.   The South had not yet begun to consider African-Americans as people – not in the slightest meaning of the word. Jones reiterates the sentiment of the doctors at the time and place with, â€Å"short of a ‘quick-fix’ by science requiring no behavior changes by blacks, there was no hope for the race† (26). The Health service claimed they informed the subjects of their disease, although an internship at the time the experiments began, Dr. J.W. Williams, stated the men received no such information.   He also claims the internships registered the data collected without understanding the nature of the experiment either (Jones 5). The term ‘racist’ as defined in the Random House Webster’s College Dictionary reads, †a belief or doctrine that inherent differences among various human races determine cultural or individual achievement, usually involving the idea that one’s own race is superior† (1072).   Given this definition, it is clear that the Tuskegee experiments were racist.   To withhold the nature of the experiments from the subjects, the name of the disease, the treatment of its symptoms and to feel no remorse in inflicting this sort of medical indictment on fellow human beings is not just racist, but also immoral and unjust. Jones points out the Health Services did investigate the treatment of these patients in an Ad Hoc committee.   The resulting medical treatments for the wives and children of the male subjects was offered with no cash restitution allowed (214).   In the end, the government did agree to $10 million dollars in payments to the â€Å"living syphiltics†, the next of kin for those already dead, â€Å"living controls† and the next of kin for the dead controls.   If you had been living with the disease and never treated, you would get a grand total of $37, 500; a paltry amount for the pain and suffering from neglect and racist bigotry (217). Works Cited Jones, James H. Bad Blood: The scandalous story of the Tuskegee experiment – when government doctors played God and science went mad. New York, NY: The Free Press, 1981. Random House Webster’s College Dictionary, 2nd Ed.   New York, NY: Random House, 1997.