#DEFINE ENTROPY PLUS#

For a variable-pressure process, the difference in enthalpy is not quite as obvious.Д®nthalpy in Extensive Units Extensive and intensive properties of medium in the pressurizer.Д®nthalpyВ is an extensive quantity, it depends on the size of the system, or on the amount of substance it contains. At constant pressure, the enthalpy change equals the energy transferred from the environment through heating (Q = H 2 вЂ“ H 1) or work other than expansion work. It is due to the fact, it simplifies the description of energy transfer. It is so useful that it is tabulated in the steam tables along with specific volume and specific internal energy. The enthalpy is the preferred expression of system energy changes in many chemical, biological, and physical measurements at constant pressure.

In many thermodynamic analyses the sum of the internal energy U and the product of pressure p and volume V appears, therefore it is convenient to give the combination a name, enthalpy, and a distinct symbol, H.

#DEFINE ENTROPY PLUS#

The enthalpy is defined to be the sum of the internal energy E plus the product of the pressure p and volume V. It is the thermodynamic quantity equivalent to the total heat content of a system. In thermodynamics, the enthalpy isВ the measure of energy in a thermodynamic system. I am one of the few people on the planet to tell you that negative entropy = life (localized), in thermodynamics this would appear in an equation as -О”s (pronounced minus delta s).What is Enthalpy Four common thermodynamic potentials. If we are still sitting here watching the cup in about 30 years when the building falls over, breaking the cup, then this too is a gain in entropy. But he had to spend more energy elsewhere to accomplish this. This would be an example of negative entropy. If he does kick us out then he will have to clean the cup, spending time and energy and hot water, to bring the cup back up to a useful higher energy state, ready for the next customer.

By this time the Barrista will probably come along to kick us out, after all we've been here 4 days and haven't actually drank any coffee. It still exists as water vapor in the room (probably attacking the wallpaper) but not in the cup. If we let the cup of coffee sit there long enough, say 4 days, we notice that some of the water that we paid for has evaporated. It still exists, but in the room not in the cup.

The heat energy that we paid for is no longer concentrated in the cup. If we let the cup of coffee sit on the table long enough, say 30 minutes, what happens? It gets cold. But today, instead of drinking it, we are going to perform an experiment. This cup of coffee is indeed a highly ordered structure in the Universe. He then pours in this fluid that contains pure (hopefully) water that has been heated (we pay the power company for the heat) and poured over these magic beans that came from far away, with many people involved with ships and trucks burning fuel so that these beans could arrive here. The Barrista, who has an understanding of what you want, then reaches for a cup that someone spent time and effort making, and someone made an effort to clean. You then walk up to the counter and order ( key word here) a hot cup of coffee. This coin is therefore concentrated time and energy or effort. You walk into a coffee shop and check your pockets that yes, you do indeed have some coin of the realm that you spent time and energy to acquire somewhere else.

Define entropy