Final answer:
Adding salt to an ice/water mixture causes a decrease in temperature due to the freezing point depression, enabling the mixture to achieve temperatures below 0°C, which is critical in various applications such as making homemade ice cream.
Step-by-step explanation:
When salt is added to an ice/water mixture, it causes the temperature of the mixture to decrease. This happens because the addition of salt lowers the freezing point of water, a phenomenon known as freezing point depression. The salt disrupts the orderly crystal structure of ice, allowing the water molecules to remain in a liquid state at temperatures where they would normally be solid.
Given that the temperature of a system does not change during a phase change, the presence of ice ensures that the system remains at 0°C during melting. However, when salt is added, the freezing point is reduced, allowing the temperature to fall below 0°C, which is useful in processes such as making homemade ice cream.
Ultimately, the addition of salt to an ice/water mixture leads to a colder mixture which can be beneficial for cooling reactions or for culinary purposes, like achieving the necessary temperatures for ice cream making without the temperature rising to 0°C too quickly.