Which of the following processes would be expected to have a positive #Delta"S"# value?

Which of the following processes would be expected to have a positive #Delta"S"# value?

A) #2"NO"_text[(g)] + "O"_2""text[(g)] -> 2"NO"_2""_text[(g)]#
B) #"Cl"_2""_text[(g)] + "Br"_2""_text[(g)] -> 2"ClBr"_text[(g)]#
C) #"N"_2""_text[(g)] + 3"H"_2""_text[(g)] -> 2"NH"_3""_text[(g)]#
D) #"H"_2"O"_text[(l)] -> "H"_2"O"_text[(s)]#
E) #"CaCO"_3""_text[(s)] -> "CaO"_text[(s)] + "CO"_2""_text[(g)]#

1 Answer
May 18, 2018

Answer:

Surely, this is #E.#?

Explanation:

An INCREASE in entropy results from an increase in DISORDER....and this is what entropy is: #"the statistical probability for disorder"#.

For #A-C# we gots entropically neutral or NEGATIVE processes in terms of moles of reactants versus moles of products. For #D# we gots the transition liquid to solid; inherently an entropically NEGATIVE process...

But for #E# we gots the evolution of a GAS, from a solid....and this should be ENTROPICALLY POSITIVE...