Answer: decrease in entropy
Explanation:
Entropy is the measure of randomness or disorder of a system. If a system moves from an ordered arrangement to a disordered arrangement, the entropy is said to decrease and vice versa.
In the given reaction:
[tex]O_2(g)\rightarrow O_2(s)[/tex]
The gaseous oxygen is converting to solid oxygen, thus the randomness is decreasing as the molecules are getting closer and the intermolecular forces are getting stronger. Thus the entropy also decreases.
