Question

Which of the following changes has a decrease in entropy?
N2O4(g) ->2NO2(g)
C6H6(l)-> C6H6(g)
2LiClO3 (s) 3O2 (g) + 2LiCl
3Fe(s) + 2O2(g) -. Fe3O4(g)

Answer 1

There is a change of decrease in entropy in 3Fe(s) + 202(g) -. Fe 304(g)
There is a decrease in a gaseous molecule, which causes a disorder in the system.

Your answer is: 3Fe(s) + 202(g) -. Fe304(g) 

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