Final answer:
A soda in a Styrofoam cup will stay cold longer than in a can on a hot summer day because Styrofoam provides better thermal insulation than aluminum. The thermal properties of the materials and the process of thermal equilibrium explain this outcome.
Step-by-step explanation:
Whether a soda will stay cold longer in a can or in a Styrofoam cup depends on the thermal properties of both materials. Aluminum, from which soda cans are made, is a good conductor of heat, meaning it can rapidly transfer heat between the soda and the surrounding environment.
On a hot summer day, this could cause the soda in the can to warm up quickly. In contrast, Styrofoam is an insulating material with a lot of air pockets, which slows down heat transfer. As a result, a soda in a Styrofoam cup would stay cold longer than in a can because the cup provides better thermal insulation.
Understanding the behavior of ice in soda also provides insight into thermal equilibrium. When soda is poured over ice, the warmer soda will transfer heat to the colder ice, causing the ice to melt and form water at 0°C. During this process, the soda and ice-water mixture will stay very close to 0°C due to this transfer of heat energy, which continues until all the ice is melted or the soda reaches the ambient temperature. In this scenario, if both the can and Styrofoam cup have ice in them, the Styrofoam cup would still maintain a colder temperature longer due to its insulating properties.