Why Does the Ocean Not Freeze?
You know that when the temperature gets really cold, any water in the area will freeze. Like when you put a glass of water into the freezer, you’ll end up with a glass of ice. The same thing applies to the outside world, so when it gets really cold in the winter time, the water in lakes and rivers can freeze. However, even if all the rivers and lakes are frozen, the ocean will still continue to be unfrozen. You’ve surely seen pictures of the Arctic region, everything is covered in snow and ice but the ocean still remains to move around. Why is that?
Maybe it’s because the water is constantly moving so it can’t freeze? Well, rivers are moving but the surface can definitely still freeze. So why is it that oceans won’t freeze even when the temperatures are so cold?
Question (Try to think of an answer to this question before you do the project.)
Why doesn’t the ocean ever freeze?
Materials You’ll Need
- 8 cups of water
- 2 tablespoons of salt
- A freezer
- A spoon
- 2 large plastic bowls
- A dry-erase marker
Procedure
- Take and label your bowls “Bowl 1” and “Bowl 2”.
- Measure out 4 cups of water and then pour the 4 cups of water into Bowl 1.
- Measure out another 4 cups or water and then pour the 4 cups of water into Bowl 2.
- Add your 2 tablespoons of salt to Bowl 2. Don’t add it all at once, pour in a little and then stir. Make sure the salt is completely mixed into the water.
- Place your bowls into the freezer and then leave them overnight.
- In the morning, check to see if the water in the bowls has frozen.
- Write down your data.
Results
In Bowl 1, the water should be frozen. In Bowl 2, the water should not be frozen.
Why?
In Bowl 2, the water has the same salt concentration levels as the ocean does. It is salt that keeps the water in the ocean from freezing! When water has a lot of salt in it, the temperature must be even colder to be able to freeze the water.
For this reason, the ocean doesn’t freeze. It has so much salt in it that it won’t get cold enough to actually turn the water into ice. Things like rivers and lakes, which are freshwater, will freeze because they don’t have a lot of salt in them! science fair project for 3rd, 4th, 5th, 6th grade students.
