When you're smack in the middle of the heat of summer which means plenty of sunshine, sunglasses and tons of summer activities. Hopefully you’re enjoying time with family and friends, outdoor parties, walks in nature and plenty of science time. After all that playing it can be fun to have an icy treat like a slushy, especially on an extremely hot day. It’s even more fun when it’s the result of a science experiment you can do at home! It takes a while to finalize and the results are a sweet surprise.
- Small plastic cup
- Large bowl
- Spoon or stirring stick
- Large straw or spoon
- Lots and lots of ice
- Favorite juice
- No contact digital thermometer if available
1. Fill the plastic cup with some juice - about halfway full. Set this in the middle of the bowl.
2. Next, add ice to the bowl, covering at least ¾ up the side of the cup.
3. Carefully sprinkle salt on the ice and do not get any in the cup of juice! You could place some plastic wrap over the cup if that helps prevent any salt mixing in the juice.
4. Now it’s time to wait! If you have a no contact thermometer, you can take readings of the ice and make note of the temperature. Don’t use your hands to touch the ice cubes because they will be too cold and can hurt your hands!
5. Stir the juice every 30 minutes. Make note of what is happening. You may notice that it takes about an hour for freezing to start. Once the freezing starts, remember to stir the juice or you might get ice cubes!
6. When the juice has reached a slushy consistency you can eat it!
Wow - Juice Becomes Slushy!
This experiment explores principles of heat transfer. When the salt is added to the ice, it causes an endothermic reaction - pulling heat from around it. This drops the temperature below freezing allowing the juice to go below freezing and turn into a slushy. You can test out different kinds of salt to see which works best, or different types of juice to see if there’s any impact on more juice or more water in the mixture. Have fun experimenting with this tasty activity.
Experiment Source: https://www.steampoweredfamily.com/activities/sweet-slurpee-science-activity-for-kids/