What is Gibbs energy. Pls explain.?
960202
In thermodynamics, the Gibbs free energy is a thermodynamic potential which measures the "useful" work obtainable from a closed thermodynamic system at a constant temperature and pressure. Under these conditions, it is zero at equilibrium.\n\nThe Gibbs free energy was developed in the 1870s by the American mathematical physicist Willard Gibbs. The Gibbs free energy is defined as:\n\n    G &#92; &#92;stackrel{&#92;mathrm{def}}{=}&#92; H-TS &#92;,\n\nwhere (in SI units)\n\n    * G is the Gibbs energy (joules)\n    * H is the enthalpy (joules)\n    * T is the temperature (kelvins)\n    * S is the entropy (joules per kelvin)
984026
You need to find the heats of formation of each species (will come from a standard table) and use this equation to get the heat of reaction:\n\n(delta)H = sum of heat of formation of products - sum of heat of formation of reactants\n\nEach heat of formation will be multiplied by its stoichiometric ratio, and the physical state will be important (especially that of water, as the heat of formation of steam is higher than that of liquid water).  You will not find a heat of formation for oxygen gas, because by definition there is no heat of formation for an element.
520018
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.
538394
This is a purely physical change of state from solid to liquid as a result of energy being added to the system.  There is an increase in entropy of the system.
723847
I am assuming that the values of H° and G° are the standard enthalpy and Gibbs free energy changes for the formation of phsogene from CO(g) and Cl2(g).\n\nFor part (a), you should already know that:\n\ndelta-G = delta-H - T*delta-S\n\nSo, for the values you are given for 298 K,\n\n-206 kJ/mol = -220 kJ/mol - 298 K * delta-S°\n-46.98 J/(mol*K) = delta-S°\n\nFor part (b), we now have (assuming delta-H and delta-S are independent of temperature) that \n\ndelta-G_601K = -220kJ/mol - 601 K * (-4.698*10^-02 kJ/mol*K)\ndelta-G_601K = -191.8 kJ/mol
930423
All energy eventually ends up as heat.  It's a consequence of the second law of thermodynamics
812302
You might just use the formula: \nEntropy of the reaction  = \n(sum of the entropy of products) - (sum of the entropy of reactants)\nIt's as simple as that :)\nThanks.
253920
Thermochemistry. It also deals with heats of formations, entropy, gibbs free energy, and spontaneity of reactions.
199900
The easiest way is to simply find literature listing delta H for the reaction.  Otherwise you have to do one of 2 things.  \n\n1. Find the enthalpy of formation for the product of the reaction which should be what you're looking for.\n\n2. Use the equation G=H-TS, plugging in the Gibbs free energy, temperature, and entropy values for the reaction,then solving for H, the enthalpy
1021437
a) \n\nThe molecules in a substance are in constant motion. Now there are two oppposing forces on a substance. One is the intermolecular bond energy that tries to keep the molecules together. The other is the kinetic energy of the molecules that tries to push the molecules apart (these two forces work together to keep substances in equilibrium - basically keeps it from exploding or imploding in simple terms).\n\nNow, in solids, the molecules have low kinetic energy but high intermolecular bond energy(IBE). Liquids, the kinetic energy is higher and conversely the IBE is lower. Gases, the kinetic energy is high and the IBE is low (makes sense - the "bond" is weak)\n\nSo now, the kinetic energy or molecules is directly proportional to the heat applied - the hotter it is, the more kinetic energy the molecules have. Therefore when you heat it ... the kintic energy gets stronger and stronger and the IBE gets weaker and weaker until it breaks and the substance undergoes its change of state.\n\nHope this explained it well!
316710
well energy is used only in the beginning to start the reaction. otherwise an exothermic reaction will give out tremendous amount of heat energy.
998070
http://en.wikipedia.org/wiki/Kinetic_energy
354239
If you are talking about heat energy then it's called an exothermic reaction.\n\nEndothermic reactions are the ones that absorb heat (i.e. they seem to cool things)
865842
Energy\n\nA chemical reaction simply supplies energy to the system
1185549
The first law of thermodynamics says that the total quantity of energy in the universe remains constant. This is the principle of the conservation of energy. The second law of thermodynamics states that the quality of this energy is degraded irreversibly. This is the principle of the degradation of energy.
159463
Thermal energy is heat that comes in 3 forms: conduction, convection, and radiation.  Conduction is when you are cooking on a stove and the heat passes through the metal in the burner and into the pan.  Convection is when air passes over a warm surface and rises or moves because of the increase in energy and takes the thermal energy with it.  Radiation is how the Sun brings energy to the Earth and other planets.  Thermal energy is measured in Joules (J for short) or British Thermal Units (BTUs).  The transfer of heat is measured in Joules per second, or watts, and BTU/hour.\n\nIts use is almost every aspect of our lives, from your body keeping itself warm to cooking to keeping your house warm to chemical reactions that generate heat.  If you want to study thermal energy, you might major in Mechanical Engineering or Physics in college.  I have a degree in Mechanical Engineering.
158024
Enthalpy (H) - The sum of the internal energy of the system plus the product of the pressure of the gas in the system and its volume: H(sys)=E(sys)+PV\n\nAfter a series of rearrangements, and if pressure if kept constant, we can arrive at the following equation: \n*H(sys)=Q at constantpressure.\nwhere *H is the H(final) minus H(initial) and q is heat\n\nI could show you much but my comp has no features.