How do you calculate entropy changes from absolute entropy values?

Kiwi: Chemistry – How do you calculate entropy changes from absolute entropy values?
Can someone please give me a basic example…? And also provide a very brief explanation and the general equation required to work this out. The difficulty is a-level, from a chemistry point of view.
10 points for the most precise and clear response.

Answers and Views:

Answer by Katie
I don’t know…… But I do know that bluberries are excellent

Answer by wicked warrior
Entropy change or delta S can be calculated if you have the delta S of the reactants and products of a chemical equation given.

using the equation :

sum of entropy of formation of ( products) – sum of entropy of formation of (reactants)

you add up the entropy of formation of reactants and subtract that from the total sum of the entropy of formation of the products.

hint you can deduce the sign of delta S by seeing the change in the number of gaseous molecules from reactants to products.

if the number of gas molecules increases then there is more disorder and hence delta S is poSitive
if the number of gas molecules decreases then there is less disorder and hence delta S is negative.

😀 hope this helps.