Ice Cream Lab Report

Title: If Salt concentration increased then more ice cream will be produced. Purpose: The purpose of this lab was to test whether a higher salt concentrate produced colder temperatures which could produce more ice cream.

Background:

- Freezing Point Depression

Freezing point depression is the process and by which adding a solvent like salt to a solute such as water. The freezing point of salt is lower than the freezing point of water, this depresses the combined freezing temperature to any temperature below freezing depending on salt concentration. Freezing point depression is categorized as a colligative property of a solution, and for dilute solutions such as saltwater; it is found to be proportional to the molal concentration of the solution.

Polarity is simply the measurement of how electronegative a substance is. Electronegativity is an atoms ability to pull electrons to itself. Ice cream is a great example of polarity. Ice cream is made by placing ice and salt around a small bag of vanilla extract milk and sugar. The salt dissolves in the ice because water is polar and salt is ionic; like dissolves in like. In order for the ice cream in the bag to be able to freeze the salt and the ice have to be combined in order to lower the temp to below freezing. If water was not polar then the salt would not be able to dissolve fully in the water/ice which would not allow for a lower freezing point therefore making it impossible to make ice cream the old fashion way.

Hypothesis: If salt concentrate is high then more ice cream will be produced?

Materials

- Plastic Gallon Bags

- Small Sandwich Bags

- 1% percent reduced fat milk (used in experiment) heavy whip cream or half and half

- vanilla extract

- sugar

- ice

- thermostat

- ml measurement system

- freezer

Procedure

1. First mix 120 mL of milk with 1 tbsp. of sugar and ¼ tsp of vanilla extract in a small plastic bag.

2. Place small plastic sandwich bag inside of a 1-gallon plastic

Ice cream produced

Summary of Results

Overall the results were extremely underwhelming, not many trends prevailed in the experiment. The data did however prove that as more salt was added more of the ice cream mix froze in the 5 minutes the bag was shaken. This was most obviously due to the combination of ice and salt providing a perfect example of Freezing Point Depression.

Conclusion:

In conclusion that data did support the hypothesis the way it was intended to. There was a slight increase in volume (+10-15mL) compared to the ice cream mix and the finished ice cream but nothing very noticeable. In trial one the ice cream content increases by 16mL when a ½ cup of salt is used, this is double the amount of salt the recipe calls for. This slight increase was probably due to an increase in frozen material as the ice cream got colder faster with all the salt. More ice cream is not produced due to colder temperatures but it was noted that ice cream doesn’t act like a liquid at all in the sense that it doesn’t expand very much if at all when frozen.

References

2. mosely, abigail. Abigail Mosely 's Digital Portfolio, Weebly,