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.

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
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: What happens to most of the energy in a trophic level as it passes to the next higher level? Answer: it is lost
As it passes to the next level, most of the energy in a trophic level it is lost.

Question: What are substances that cannot be broken down into simpler substances with different properties called? Answer: elements

Substances that cannot be broken down into simpler substances with different properties are called elements.

