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Chapter 4: 4.37 (page 148)

A common (but imprecise) way of stating the third law of thermodynamics is "You can't reach absolute zero." Discuss how the third law, as stated in Section 3.2, puts limits on how low a temperature can be attained by various refrigeration techniques.

Short Answer

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The refrigeration techniques cannot attain absolute zero temperature

Step by step solution

01

Given Information

Given techniques: refrigeration techniques

How low a temperature can be attained by various refrigeration techniques

02

Explanation

As per the Third law of thermodynamics, entropy of the system tends to zero at absolute zero temperature.

As entropy approaches zero at absolute zero temperature therefore the heat capacity also goes to zero. This means that the heat capacity becomes negligibly low at very low temperature.

So the cooling process becomes ineffective for very low heat capacity. This is the reason why refrigeration requires temperature higher than absolute zero.

So we can say that the refrigeration techniques cannot attain absolute zero temperature.


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Most popular questions from this chapter

Table 4.5 gives experimental values of the molar enthalpy of nitrogen at 1 bar and 100 bars. Use this data to answer the following questions about a nitrogen throttling process operating between these two pressures.

(a) If the initial temperature is 300K, what is the final temperature? (Hint: You'll have to do an interpolation between the tabulated values.)

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