what is exergy and its formula?
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Please go to this website to find your answer:\nhttp://en.wikipedia.org/wiki/Exergy\n\nIn thermodynamics, the exergy Ξ of a system with respect to a reservoir is the maximum work done by the system during a transformation which brings it into equilibrium with the reservoir.[1] The term was coined by Zoran Rant in 1956. The concept, however, has existed since W. Gibbs (1873), i.e. ‘available energy of the body and medium’, and G. Gouy (1889), i.e. ‘possibility of obtaining work’.\n\nThe term exergy is also used, by analogy with its physical definition, in information theory related to reversible computing. Exergy is also synonymous with: availability, available energy, exergic energy, essergy (considered archaic), utilizable energy, available work, maximum (or minimum) work, reversible work, and ideal work.\n\nExergy of heat available at a temperature\nCarnot efficiency is\n\n n = 1-(T<c>/T<h>)\nwhere TH is the higher temperature and TC is the lower temperature, both as absolute temperature. From Equation 1 it is clear that in order to maximize efficiency one should maximize TH and minimize TC.\n\nFor calculation of exergy of heat available at a temperature there are two cases: the body releasing heat is higher than the surrounding, or, the temperature of the body is lower than the surrounding.\n\nExergy fraction of heat available at a temperature higher than the surrounding is:\n\nE/Q = 1 - (T<o>/T<h>)\n \nwhere Th is the temperature of the heat source, and To is the temperature of the surrounding.\n\nExergy of cold is though:\n\nE/Q = 1 - (T<c>/T<o>) \n\nwhere Tc is the temperature of the cold body that is receiving heat from the surroundings.
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space shuttle burns hydrogen. imagine you're standing under it when it launches. endothermic or exothermic?\n\ncorrect reaction formula was already given.
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51kg x 25 m = energy used\n\ndivide the energy used by 0.30 to get the second answer
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you will need its specfic heat of coal by searching abt it.\nthe formula for calculating heat energy is\n\nq=m *c *(t2-t1)\n take SI units . the temperature differene is 200 and m is 1 kg of coal .if specific heat c is 1, then heat energy will be 200 joules/.
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one mole of water formation will be as follows:\n\nH2 + (1/2) O2 -------> H2O + 68.3 Kcal.\n\nIts highly exothermic reaction.\nNow, if you want the reverse to happen, you need to give the same amount of energy to break the bonda between H and O
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initial energy : (mv^2)/2 = (0.047*56^2)/2 = 73.696 J\nfinal energy : mgh +KE= 0.047*9.81*17 + KE = 73.696\n\nKE = 73.696 - 7.83819 = 65.85781 = (mv^2)/2\nv = squareroot(KE*2/m)\nv= 52.94 m/s
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The sum of the internal energy of a body and the product of its volume multiplied by the pressure.
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There are actually four laws:\n\nZeroth Law: "If two thermodynamic systems A and B are in thermal equilibrium, and B and C are also in thermal equilibrium, then A and C are in thermal equilibrium."\n\nFirst Law: "The increase in the internal energy of a system is equal to the amount of energy added to the system by heating, minus the amount lost in the form of work done by the system on its surroundings."\n\nSecond Law: "The total entropy of any isolated thermodynamic system tends to increase over time, approaching a maximum value."\n\nThird Law: "As a system approaches absolute zero of temperature all processes cease and the entropy of the system approaches a minimum value or zero for the case of a perfect crystalline substance."
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The formula would be 2HCL+ CaCO3 ---> CaCl2 + H2O + CO2. The standard enthalpies of formation are -167.2, -1207, -796, -285.8, and -393.5 respectively. When you use the formula "Sum of products minus sum of reactants, you come up with +66.1 (don't forget to multiply the HCl formation by 2 for 2 moles). I am assuming that the HCl you are talking about is HCl (aq) and not HCl (g). If it is a gas, then the standard enthalpy of formation is -92.31, so you would come up with a different number (-83.68)\n\nIf it is aqueous HCl, you come up with a positive 66.1 kJ/mole, which means that heat was absorbed by the reaction (endothermic). That probably means your cylinder would feel cooler, since heat is being taken in by the reaciton.\n\nIf you mean gaseous HCl, you come up with a negative 83.68 kJ/mol, which means that heat was given off by the reaction (exothermic). That probably means yoru cylinder woudl feel warmer, since heat is being given off by the reaciton and taken in by the cylinder.
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Delta E is a term used to describe change in internal energy which is the sum total of the kinetic and potential energies of the constituent particles.Internal energy can be changed only by allowing heat to move in/out of the system or by work done on/by the system.It is often defined as the heat absorbed at constant volume. Heat change at constant pressure is what we call change in enthalpy or delta H.
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Props to mathematician.  To expand, a "machine" must transform energy in some way.  The second law of thermodynamics describes that any time energy is transformed, entropy is created.  Whenever entropy is created, the "machine" must expel some energy in order to expel the entropy that has been created (if it doesn't expel the entropy, the machine doesn't run).  So every time a machine does something, it MUST lose some energy, and it cannot run forever.
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Thermochemistry. It also deals with heats of formations, entropy, gibbs free energy, and spontaneity of reactions.
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Start with formula for total energy (the derivation of this is pretty awful and requires lots of diagrams to explain it)\n\nSo total energy is g*m*c^2 [g is gamma factor 1/sqrt(1 - V^2/c^2)]\n\nThe kinetic energy is total energy minus internal energy of particle = g*m*c^2 - m*c^2 (1)\n\nNow expand the gamma factor as a binomial series:\n\ng = 1/sqrt(1 - V^2/c^2) = 1 + (v^2/2*c^2) + ...\n\nsubstitute this into the above equation (1) and you get\n\nkinetic energy = m*c^2(1 + v^2/2*c^2) - m*c^2\n\n= 1/2*m*v^2\n\n(This is an approximation - so this only applies for low velocities. For relativistic velocities use formula (1) or expand the binomial expression to higher degrees of 'v')
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DH reaction = DH products – DH reactants\n\nExample:  2A + B -- C\nDH = DH C – (2 DH A + DH B)\n\nIf DH is negative: exothermic reaction \nIf DH is positive: endothermic reaction
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exothermic is describes the release of energy\n\nendothermic describes the absorption of energy
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It is exothermic when the rxn. Heat is negative\nConsider Thermite\n\n2Al(s) + Fe2(O3)(s) –> Al2(O3)(s) + 2Fe(l) ∆Hºrxn=-847.6kJ
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detlaH=H(products) - H(Reactants)\n\n200KJ/mol