It is warm outside and kids are going to the beach (where there is salt water) and the pool. Some kids may notice that they float better in salt water than in fresh water. After doing this experiment, your child will know why this occurs. Explore the difference in density between salt water and fresh water with this easy experiment.
Let’s Get Started!
- 2 Glasses of Water
- Food Coloring
- Place a few ice cubes into one glass of water
- Add a few drops of food coloring into the ice water.
- Add several tablespoons of salt to the other glass of water and stir so it dissolves.
- Add some ice cubes to the salt water glass.
- Add food coloring to the salt water and see what happens.
- Compare the food coloring in the fresh and salt water.
Why it Works:
- Saltwater is denser than fresh water because the sodium chloride is dissolved in it.
- Specific amounts of salt water is heavier than the same volume of freshwater.
- When salt is dissolved in water, like at the ocean, the salt adds to the mass of the water.
- The salt makes the water denser than it would be without the salt.
- When salt is dissolved in water, as it is in ocean water, it adds to the mass of the water and makes the water denser than it would be without salt. Because objects float better on a dense surface, they float better on salt water than in fresh water.