Chemical Reactions of Making Ice Cream

  Certain substances affect the state of ice. When salt is sprinkled on ice, for example, it causes the ice to melt. This chemical reaction is actually a heat energy transfer. Water freezes at 0°C. A saturated saltwater solution freezes at -32°C. What happens if you sprinkle salt on ice? The salt will dissolve in the water; It disrupts it's equilibrium. Fresh water freezes at 0 degrees C. Salt water freezes at lower temperatures, depending on how much salt is in the water. As the ice melts to water, the change from solid to liquid requires heat. This is just like when water changes from liquid to gas, for example when evaporating sweat cools your skin. As ice melts, the heat is taken from the ice and water around it.Therefore, both get colder.

 *1/2 cup milk
 *1/2 cup whipping cream
 *1/4 cup sugar
 *1/4 teaspoon
 *3/4 cup rock salt
 *2 cups ice
 *1- quart Ziploc bag
 *1- gallon Ziploc bag
 *Thermometer
 *Measuring cups and spoons
 *Cups and spoons for eating your treat

1. Add 1/4 cup sugar, 1/2 cup milk, 1/2 cup whipping cream, and 1/4 teaspoon strawberry to the quart Ziploc bag. Seal the bag securely.

2. Put 2 cups of ice into the gallon Ziploc bag.

3. Use a thermometer to measure and record the temperature of the ice in the gallon bag.

4. Add 1/2 to 3/4 cup salt to the bag of ice.

5. Place the sealed quart bag inside the gallon bag of ice and salt. Seal the gallon bag securely.

 6. Gently rock the gallon bag from side to side. It's best to hold it by the top seal or to have gloves or a cloth between the bag of your hands because the bag will be cold enough to damage your skin.
7. Continue to rock the bag for 10-15 minutes or until the contents of the quart bag have solidified into ice cream.

8. Open the gallon bag and use the thermometer to measure ad record the temperature of the ice/salt mixture.

 9. Remove the quart bag, open it, serve the contents into cups with spoons and ENJOY!

1.)What kind of ice cream are you making? Strawberry.

2.)Document the temperature of the ice in the gallon bag before adding the salt. 0 degrees C 

3.)Document the temperature of the ice/salt mixture (Not the ice cream) in the gallon bag when the ice cream mixture begins to solidify. -10 degrees C

4.)What is the temperature difference before adding the salt and after mixing for 5 minutes? -10 C

5.)What is the temperature difference before adding the salt and after mixing for 10 minutes? -10 C

 1.) What kind of chemical reaction is the process of ice cream making, as done in our lab? Explain why. The reaction gives off heat so it is a exothermic reaction.

 2.) Explain why salt water is harder to freeze than plain water. Saltwater has a much lower freezing point than freshwater does.

 3.) Is the process of making ice cream a physical or chemical change? Explain your answer. Making ice cream is a physical change, not a chemical change, because nothing new
was created. The ice has just changed its state of matter.

 4.) Why is salt used with the ice instead of sugar? The ice and salt causes the ice cream to thicken, which then turns into a tasty after the experiment.

                                                   

                                                        Works Cited:

http://www.benjerry.com.sg/flavors/from-cow-to-cone;jsessionid=1D0A1408E2327D52ADD41A999D8C2B7B

https://www.uoguelph.ca/foodscience/dairy-science-and-technology/dairy-products/ice-cream/ice-cream-structure/structure-ice-crystals