Question

A few pieces of dry ice, CO2(s), at -78°C are placed in a flask that contains air at 21°C. The flask is sealed by placing an uninflated balloon over the mouth of the flask. As the balloon inflates, the dry ice disappears and no liquid is observed in the flask.

State the direction of heat flow that occurs between the dry ice and the air in the flask.
Write the name of the process that occurs as the dry ice undergoes a phase change in the flask. [1]
Compare the entropy of the CO2 molecules in the dry ice to the entropy of the CO2 molecules in the inflated balloon.

Answer 1

The direction of heat flow is from surroundings to system (air to ice), the dry ice is subliminating.

Answer 2

• Heat flows from the air into the dry ice.
• Sublimation (its when a solid becomes a gas without becoming a liquid first).
• CO2 molecules in gaseous phse has more entropy than in solid phase.

Step-by-step explanation:

• To sublimate dry ice needs to fain energy, wich is provided by the surrounding air.
• Solid is the more condensated state of matter, so it has less entropy than any other state of matter.