Food Coloring Race

Did you ever hold a food coloring race as a kid?  No?  Me neither.  Through an online search I found this cool science experiment.  In this experiment you are testing to see whether food coloring disperses faster in cold water or hot water.  All you need for this is experiment is a jar/cup of cold water, a jar/cup of hot water, and food coloring.  Then place a drop or two of food coloring in each jar at the same time and watch how quickly the food coloring disperses.

As you can see from our video, the food coloring in the hot water disperses much more quickly than the food coloring in the cold water.  Despite the fact that I dropped the food coloring in the cold water just before the hot water, the hot water food coloring still wins the battle.

So why does food coloring disperse more quickly in hot water?  In hot water, the water molecules are moving around faster than the molecules in cold water.  This is related to the definition of temperature.  Hotter objects contain molecules that have more energy and move faster.  Because the molecules move faster, they carry the food coloring a greater distance more quickly.  As a result, your eye sees the food coloring spreading throughout the jar more quickly.

My 6 year old thought this was cool.  My 2 year old, not so much.  She was mad about her missing dollar as you can hear in the background of the video!  I guess I'd be mad too if I lost my money!  :-)