Question

A 12-ounce soft drink weighs about 0.35 kilograms. Assume that on a hot day a can of soft drink is cooled in a container of liquid water in equilibrium with ice. There is enough ice in the container so that the temperature of the ice water stays constant at 0 0 C and the ice-water can be considered a heat sink. Model the soft drink with the properties of water, assuming it has an initial temperature of 30 0 C and a final temperature of 5 0 C, and has a constant specific heat capacity of 4.2 kJ/kg/K.

a)The amount of heat transfer in kJ from the single can of soft drink to the ice-water.

b) The total change in entropy of the ice-water

c) The total change in entropy of the can of soft drink

d) The total change in entropy of the universe (Sgen) caused by this process.

Ice-Water Ti = 0 °C Soft Drink Ti = 30 °C T2 = 0°C T2 = 5°C

Answer 1

Guven : Mast & Soft dünk - m=0.35 35 kg for I Ce wates specific Heat - CF 4.2 kJ / kg 1k Tia Tazoc for Soft Drink T, = 30°c = 303k T = 5°c = 298k Amount Heat energy . d= m GOT AT = Ti-T T- T = 5k 0.35 kg x 4.2 kJ /kg (k*5* 7.35 kJ s = As We know that do= dot Pdv and as= do do te du a dT t Pau T T T 2 R du T P R. T a ln Tz + R ln V₂ T V V =h same T Here

ss- for ice water a ln ( 7 / / (4.2 KJ /kg Ik ). In [ T = 72 = 0°c © Change entropy for lice For lice water) Soft drink Asa a In The (os a ln (1) = of for I he water. in 7 - 2 298 303 ss= 4.2 X 40.0/75) KJ / kg Ik 72.01 J / kg Ik] - For Soft Drink 0.07201 [ = - 72.01 J Total in change entropy of Universe A Suniverse Asice water tos Soft drink ot (-72-01 Il tylk ) Ikylk) Sonieuse 1) - 72.01 J