Surface Area
One of the major things that determines the rate of many chemical and physical changes is the amount of surface area where the reaction takes place. For an easy way to see that, you will need:
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solution ?mystery?
Hi there Happy Scientist,
Last week I wanted to demonstrate to my class that hot water would "stir" up a drop of food coloring faster than cold water and in two trials, just the opposite happened....I dropped the food coloring from right above the water level and the food coloring I put into the hot water fell right to the bottom of the cup....and the food coloring started moving around more in the cold water cup.....any idea why this may have happened? -Mystery in room 102
RE: Mystery in room 102
Marvelous observation!
The drop of food coloring at room temperature was denser than the hot water, so it sank to the bottom, and stayed there until the temperature (and density) equalized. I suspect that your other sample was room temperature, pretty much the same as the food coloring. That means that they both had the same density, so diffusion happened faster.
So the temperature difference in the hot water added another variable, density.
You can control this by putting a bottle of food coloring in the hot water to heat it to the same temperature as the water. Then you can compare hot coloring in hot water with cold coloring in cold water, and should get results that are more what you were expecting. Let me know how it works.
science project
what if you did food coloring in water and put it in the sun will the food coloring stay and the water evaporate or will the food coloring evaporate with the wate why or why not.
The color in food coloring
The color in food coloring does not evaporate, so it would be left behind.
Thanks!
Thanks!
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