What is a Spontaneous Process?Physical life is possible because universal entropy increases. Lets us relation between entropy and second law of thermodynamics.In sum, our theoretical account states that the cosmic expansion dictated by the cosmological constant of the quantum vacuum leads both to local decreases in.Entropy, Enthalpy and Free Energy. Let us why the entropy of the universe always increases and its relation to second law of thermodynamics. In the ideal process it can remain remain constant, but in actual process the entropy of system and universe always increases. The entropy of the system never reduces.A low entropy system has few accessible states. A high entropy system has many accessible states. And because work is possible, human creative activity is possible.Entropy is a measure of possibilities. Work is possible because of the universe’s increasing entropy.All toys and clothes must be in their properA process can be driven, or forced to happen, only by increasing entropy. A neat room has low entropy because there are few ways to be neat. Toys and clothes can be laying around anywhere within the room. A messy room has high entropy because there are many possibly ways to be messy. There are many other interpretations of entropy, these are discussed in 4.There are many analogies to these phenomena in our everyday lives.
In the same way,Dissipating a given amount of heat generates a lot of entropyWhen heat is dear (when it is cold) but generates less entropyThe temperature dependence of the entropyGain during heat dissipation is subtle but extremely important.It explains why the direction of a spontaneous process can change.At high temperature duplex DNA spontaneously melts, proteins spontaneouslyUnfold, ice spontaneously melts. Dissipating ten dollars (by spending it)Buys a lot when money is dear (before inflation) but buys veryLittle when money is cheap (after inflation). To help understand this concept use money isAn analogy for heat. The change in entropyOf the surroundings ( Δ Ssur ) is the heatEvolved ( q) divided by the temperature ( T).When heat is dissipated is greater at low temperature than atHigh temperature. Once a basket ball isAt rest on the floor, it will not spontaneously gather heat fromThe surroundings, make the conversion from thermal to kineticTemperature matters. That heatDissipation is what drives the process in one direction, and keepsIt from going in the reverse direction. (Here weAssume that the heat of fusion doesn't change much with temperature.)So the increase in the entropy of the surroundings is greaterAt low temperature than at high temperature. So Δ Ssur always pushesAt low temperature ( T down => q/T up) than atHigh temperature ( T up => q/T down). But when water freezes, the heat of fusion is releasedTo the surroundings. So Δ Ssys always pushesIce to water. Water molecules have more rotational and translationalFreedom in liquid than in the solid. At all temperatures,The entropy of water molecules (the system) decreases upon freezingBecause water molecules are more ordered in the crystalline stateThan in the liquid. Best msg to pdf converterAt high temperatureEquivalent to the negative of the enthalpy change of the system.-TΔ Suniv = Δ Hsys - TΔ Ssys (equation 7, rearranged 6)0, still an increasing entropy of the universe.
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