Can Water float on Water

Can Water float on Water

• Water covers 70% of Earth’s surface. The water of the oceans is not uniform. Climatic processes create large-scale differences in ocean water temperature and salinity.

• The goal of this project is to investigate what happens to layers of water with different densities when they are brought together.

• Hypothesis: Saline and cold water are denser than fresh and warm water.

Can Water Float on Water?

• In this project, I will experiment to see what happens when layers of water at different densities are brought together. I will create “two layers” in plastic bottles, color them with different food colors to tell them apart.

• I will then bring the two layers together by flipping one bottle over on top of the other.

• Materials: clear bottles. Table salt, food coloring, hot and cold water. Thermometer.

Deep Ocean salinity ranges from 32 to 37.5 parts per thousand.

• My ocean water for this experiment will be approximately 32-37.5 to mimic ocean water.

• 1tsp of salt weighs approximately 6g.

• I will mix 32 oz of water to 6tsps of salt, this will give me approximately 36ppt.

• For the “Fresh” water I will use tap water.

The red liquid is Saline and the blue liquid is “fresh”. After 10 minutes the liquid stayed the same.

In this experiment, I put the saline water on top of the fresh water. After 10 minutes the saline had changed places and sank to the

bottom of the bottle.

Evidence of mixing. Schlieren lines are wavy lines caused by changes in the index of refraction of the solution.

In this experiment the yellow bottle is tap water (temp 50 degrees) and the green is cold water. After 10 minutes the water stayed the

same.

In this experiment I put the cold water on top. After 10 minutes the cold water had sunk to the bottom .

Results:• Experiment 1: Fresh water on top of salt water. The

liquids stayed the same after 10 minutes proving that salt water is denser than fresh.

• Experiment 2: Saline on top of fresh. The saline sank to the bottom, proving that salt water is denser than fresh.

• Experiment 3: hot water on cold water. The liquids stayed the same, proving that cold water is denser than warm.

• Experiment 4: Cold water on warm water. The cold water sank to the bottom, proving that cold water is denser than warm.