Analyzing Amount Of Salt Affects The Freezing Point Of Ice Cream

Title

Does the amount of salt in an ice cream mixture affect the freezing point of ice cream?

Purpose

The purpose was to observe how the addition of salt affects the freezing point of ice cream.

Background Information Water is made of water and hydrogen molecules, when bonded, they form a crystalline structure called ice (worldofchemicals.com). During the change of water from a liquid to a solid, water molecules move slow so they can’t leave the intermolecular attraction between water molecules. Ion-dipole forces occur between water molecules and a sodium ion. The slightly negative charge of oxygen in water is attracted to the positive charge of the sodium ion (courses.lumenlearning.com). During the change of water from a liquid to

When you go to a lake in the winter with that same temperature, the lake may be frozen in some spots. Why does the ocean water not freeze at the same temperature as fresh water? The ocean water has a lower freezing point than fresh water because there is salt in ocean water. The freezing point of the ocean water is about -2 degrees Celsius (oceanservice.noaa.gov).

Most ocean water has about 7 teaspoons of salt in 1 liter of water (sciencelearn.org.nz). The higher the concentration of salt the lower the freezing point of water.

The freezing point of a substance is the temperature at which a substance usually liquid, becomes a solid. Water has a known freezing point of zero degrees Celsius. In certain circumstances it may be necessary to lower the freezing point of a liquid. One example of lowering the freezing point is when the roads are salted in the winter before ice or snow storms. The salt applied to the roads causes the ice to stay liquid at temperatures below 0 degrees Celsius. Another example of lowering the freezing point is when homemade ice cream is made with milk and sugar with salt and ice added around the container. The salt and ice solution, called brine, lowers the freezing point and changes the milk and sugar combination to form ice cream. In both of these situations salt is used as a solute and the ice is the solvent. The solvent dissolves the solute. When adding more of the solute and increasing the concentration, the freezing point is