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: In humans, what is the first organ to form and become functional? Answer: heart

Answer: In humans, the heart is the first organ to form and become functional.


Question: Question: What are cations simply named after? Answer: the parent element

Answer:
The parent element are cations simply named after.