I Like Salt with My Carrots! (20 pts)
Problem: (2 pts) In which direction do water molecules move during osmosis?
In which direction do molecules move in diffusion?
Hypothesis: (2 pts) I think molecules move from an area of ____ (high, low)
concentration to ____ (high, low) concentration.
Procedures:
Part one: Diffusion
1. Place 200 ml of water into a beaker. Let sit for 1 minute until the
water is still.
2. Add three drops of food coloring to the water.
3. Record your observations.
Part Two: Osmosis
1. Tie a string around each of the two carrots (tightly!).
2. Label your string on the tape with your period number.
3. Place one carrot into the fresh water beaker and place the other
one into the salt water beaker.
4. Leave for 24 hours. Record your observations.
Results:
Diffusion: (3 pts)
Draw a picture with arrows showing what happened when you put the food
coloring into the water.
Osmosis: (4 pts)
Observations Day 1
Observations Day 2
Fresh water
Salt water
Questions: (7 pts) (2 pts-write in complete sentences)
1. When did the food coloring in the water stop moving?
2. How did the food coloring move in the water?
3. Describe the movement of water molecules in the fresh water.
4. Describe the movement of water molecules in the salt water.
5. What would happen to a red blood cell if it were placed in salt
water (think about what happened to the carrot)?
6. How is diffusion similar to osmosis?
7. How is diffusion different from osmosis?