Title: Diffusion
Diffusion is the spontaneous movement of particles from where they are more concentrated to where they are less concentrated. For this experiment, a 14 cm glass was filled with cold tap water. A drop of red food coloring was dropped in the cup. A stopwatch was used to measure the time it took for the food coloring to get to the bottom of the cup. The average diffusion rate was .78 cm a second. If a different color was used, I do not think it would have made a difference in the results. The mood of the person experimenting could possibly alter the results. For example, if a person is under stress, they may accidentally squeeze too much altering the rate of diffusion. If the water was warmer, this may have sped the diffusion process because the molecules would have been moving faster. If the water was freezing, this may have slowed the diffusion process because the molecules may have been moving slower.
Part B:
Title: The effect of salt concentration on osmosis in potato.
Introduction:
1. The purpose of doing this lab is to observe the effects of various solute concentrations on osmosis in a potato. 2. During osmosis, water moves from the side of the membrane where they are most concentrated to the side where they are less concentrated. If the concentration is equal on both sides, there will be no movement. 3. I hypothesize that the mass of the potato will decrease as the salt in the solution increases. This is because the solution around the potato will draw the water from the potato, causing it to decrease in size. Method:
To begin this experiment, 1½ teaspoons of salt was added to a beaker containing 100 mL of distilled water. This was the 7% solution. 50 mL of this solution was poured into a second beaker and 50 mL of distilled water was added. This produced the 3.5% solution. 50 mL of this solution was added to a third beaker, then 50 mL of distilled water was added to make the 1.75% solution. Out of