Third Law of Thermodynamics The entropy

A disordered state of a system (state of high entropy) can be achieved in more ways (W) than an ordered state and is therefore more probable. The entropy of a state can be calculated from Boltzmann s formula, S = k In W. According to the third law of thermodynamics, the entropy of a pure, perfectly ordered crystalline substance at 0 K is zero. 

Third law of thermodynamics The entropy of a pure substance in a perfect crystalline state is zero at absolute zero. 

According to the third law of thermodynamics, the entropy of a perfect crystal should be zero at 0° K at all pressures hence, it follows that... 

Third Law of Thermodynamics The entropy of a hypothetical pure, perfect, crystalline substance at absolute zero temperature is zero. 

Finally it is appropriate to consider the third law of thermodynamics briefly in connection with the detennination of entropy values. So far we have related entropy to molecular disorder—the greater the disorder or freedom of motion of the atoms or molecules in a system, the greater the entropy of the system. The most ordered arrangement of any substance with the least freedom of atomic or molecular motion is a perfect crystalline substance at absolute zero (0 K). It follows, therefore, that the lowest entropy any substance can attain is that of a perfect crystal at absolute zero. According to the third law of thermodynamics, the entropy of a perfect crystalline substance is zero at the absolute zero of temperature. As the temperature increases, the freedom of motion also increases. Thus the entropy of any substance at a temperature above 0 K is greater than zero. Note also that if the crystal is impure or if it has defects, then its entropy is greater than zero even at 0 K because it would not be perfectly ordered. 

Third law of thermodynamics. The entropy of a perfect crystalline substance is zero at the absolute zero of temperature. (18.2)... 

Figure 4.2. As we approach absolute zero, the slope of the curve approaches zero as required by the third law of thermodynamics. (The entropy of any pure substance in complete internal equilibrium is zero.) An empirical relationship that fits the data for several ceramics is...

According to the third law of thermodynamics, the entropy of a perfect crystalline substance is zero at the absolute zero of temperature. As the temperature increases, the freedom of motion increases and hence also the number of microstates. Thus, the entropy of any substance at a temperature above 0 K is greater than zero. Note also... 

Where does one travel next at the intersection There were comers notably untouched third-law consequences, phase rule applications, and critical phenomena, to name three. These justihably warrant full-scale treatments. By the third law of thermodynamics, the entropy and heat capacity of a crystalline system converge to zero in the limit of zero absolute temperature. According to Boltzmann ... 

The third law of thermodynamics—the entropy of a perfect crystal is zero at... 

The third law of thermodynamics The entropy of a system approaches a constant value as the temperature approaches zero. The entropy of a system at absolute zero is typically zero and, in all cases, is determined only by the number of different gronnd states it has. Specifically, the entropy of a pure crystalline substance at absolute zero temperature is zero. 

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