Answer:
b. nonspontaneous .
Step-by-step explanation:
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In this case, by considering the given description, it is possible for us to realize this process is b. nonspontaneous because the molecules of the gas are going to tend to spread all around the flasks instead of convening together unless an external force was applied. In such a way, this cannot be spontaneous as it will occur without any external action, and the concepts of exergonic and endothermic are specifically for chemical reactions.
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