Question

Consider the following questions about ice cream based on energy changes of solution formations:
a. Is the making of ice cream increasing or decreasing entropy?
b. If the ice cream ingredients mixed together is the chemical system, is it an exothermic or endothermic process to convert them to ice cream?
c. The principle behind an ice cream freezer is that when salt is added to the ice, the melting ice absorbs heat from the ice cream, and the ice cream freezes. What drives the spontaneous melting of ice when it is mixed with salt?

Answer 1

answers are based on energy changes of solution formations ( iceceam/ solution as system )
a. Is the making of ice cream increasing or decreasing entropy?

Decreasing entropy , since dQ < 0 ( heat loss) , thus as per definition of entropy , dS = dQ / T

dS = -ve
b. If the ice cream ingredients mixed together is the chemical system, is it an exothermic or endothermic process to convert them to ice cream?

since there is decrease in temperature , dQ = -ve ( heat loss) ==> exothermic process
c. The principle behind an ice cream freezer is that when salt is added to the ice, the melting ice absorbs heat from the ice cream, and the ice cream freezes. What drives the spontaneous melting of ice when it is mixed with salt?

   Addition of salts lowers the melting point of ice , as per principles of colligative properties (depression on melting point).