In which example does entropy increase?
i. a piece of fruit freezes in liquid nitrogen.
ii. librarians put library books back onto shelves at the end of the day.
iii. liquid nitrogen boils in a beaker at room temperature.
iv. dry ice sublimes.
v. a balloon collapses as its contents cool in liquid nitrogen.

Explanation:

Entropy -

In a system, the randomness is measured by the term entropy .

Randomness basically refers as a form of energy that can not be used for any work.

The change in entropy is given by amount heat per change in temperature.

entropy increases as the randomness increase ,

and ,

entropy decrease as the randomness decreases .

I. A piece of fruit freezes in liquid nitrogen.

randomness decreases , and so entropy decrease .

II. Librarians put library books back onto shelves at the end of the day.

randomness decreases , and so entropy decrease .

III. Liquid nitrogen boils in a beaker at room temperature.

change in state from less random liquid to gas , randomness increases , hence entropy increases

IV. Dry ice sublimes .

change in state from less random solid to gas , randomness increases , hence entropy increases .

V. A balloon collapses as its contents cool in liquid nitrogen .

cooling process , reduces the randomness , hence , entropy decreases .

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.