Effect of Temperature
1. Before you begin, read the experiment below and create a hypothesis regarding the rate
of diffusion of food coloring in hot and cold water.
Hypothesis:
Hotter water will diffuse food coloring quicker that cold water.
2. Add approximately 9 cm of very cold water (3.5 in) to one glass and 9 cm of very hot
water to another.
3. Place the glasses in a location where they can remain undisturbed. Allow the glasses to
remain undisturbed for at least 2 minutes before proceeding to the next step.
4. Carefully place one small drop of food coloring on the surface of the water in the
center of each glass. Care should be taken not to touch the glasses or disturb the
water when adding the food coloring. The water should be as still as possible.
5. Observe the pattern of diffusion from the side. Do the glasses differ?
Yes! The food coloring diffuses MUCH quicker in the hot water. The food coloring
also diffuses in all directions in the hot water. In the cold water, it sinks straight
down.
6. Estimate the percent of water in the glass that is covered every 30 seconds for 5
minutes. Initially (time = 0 sec.) there will be 0% colored. Round your answers to the
nearest 10 percent (10%, 20%, 30%, etc.). The results section of your report should
contain a graph of these results.
Time Cold Hot
Elapsed
0 0 0
30 10 70
60 10 70
, 90 10 80
120 10 90
150 10 90
180 10 90
210 10 90
240 10 90
270 10 90
300 10 90
1. Before you begin, read the experiment below and create a hypothesis regarding the rate
of diffusion of food coloring in hot and cold water.
Hypothesis:
Hotter water will diffuse food coloring quicker that cold water.
2. Add approximately 9 cm of very cold water (3.5 in) to one glass and 9 cm of very hot
water to another.
3. Place the glasses in a location where they can remain undisturbed. Allow the glasses to
remain undisturbed for at least 2 minutes before proceeding to the next step.
4. Carefully place one small drop of food coloring on the surface of the water in the
center of each glass. Care should be taken not to touch the glasses or disturb the
water when adding the food coloring. The water should be as still as possible.
5. Observe the pattern of diffusion from the side. Do the glasses differ?
Yes! The food coloring diffuses MUCH quicker in the hot water. The food coloring
also diffuses in all directions in the hot water. In the cold water, it sinks straight
down.
6. Estimate the percent of water in the glass that is covered every 30 seconds for 5
minutes. Initially (time = 0 sec.) there will be 0% colored. Round your answers to the
nearest 10 percent (10%, 20%, 30%, etc.). The results section of your report should
contain a graph of these results.
Time Cold Hot
Elapsed
0 0 0
30 10 70
60 10 70
, 90 10 80
120 10 90
150 10 90
180 10 90
210 10 90
240 10 90
270 10 90
300 10 90
