Question

which of the following is a process with a negative ΔS?

a)CaCO3(s) → CaO(s) + CO2(g)

b)CO2(s) → CO2(g)

c)None of the choices are correct because ΔS cannot be negative.

d)dissolving sugar in water

e)H2O(l) → H2(s)

Answer 1

The only reaction there that has a negative delta S is H2O(l) going to H2(s). That is because liquids have more entropy than solids therefore the change is negative since you are going from a higher state of entropy to a lower state of entropy. However, I don't know if that reaction is possible. For one, the oxygen disappears and two, liquid hydrogen is really hard to make. I don't think a reaction can produce it.

Answer 2

The process with a negative Δs is : ( e ) H₂O(l) ----> H₂(s)

Reactions with negative entropy values are reactions involving the movement from a higher state of entropy to a lower state of entropy. for example : The formation of water from the combination of hydrogen and oxygen.

Gases have a higher entropy state than liquids and liquids have a higher entropy state than solids and this is because the molecules of solids are more ordered and do not move freely like the molecules of liquids and gases.

Therefore liquids have a higher entropy state when compared to solids and the process of converting a liquid to solid produces a negative entropy value.

Hence we can conclude that The process with a negative Δs is : ( e ) H₂O(l) ----> H₂(s)

Learn more about entropy : https://brainly.com/question/2722633