In this task, you are given a question and an answer, you would be asked to create the sentence based on the Question-Answer provided. It should be contained within the Question-Answer provided.
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Question: Question: Expansion of a gas into a vacuum is irreversible because the external pressure is measurably less than the internal pressure of the gas, and no states of what exist? Answer: equilibrium

Answer: Expansion of a gas into a vacuum is irreversible because the external pressure is measurably less than the internal pressure of the gas, and no states of equilibrium exist.


Question: Question: The properties of the alkali metals are similar to each other as expected for elements in the same what? Answer: family

Answer: The properties of the alkali metals are similar to each other as expected for elements in the same family.


Question: Question: Mammals have four limbs and produce what kind of eggs? Answer: amniotic

Answer:
Mammals have four limbs and produce amniotic eggs.