Two Beakers, Hot and Cold Water, Food Coloring

 

Code Number: 4D50.60

Demo Title: Diffusion - Liquids

Condition: Good

Principle: Pressure Diffusion

Area of Study: Thermodynamics

Equipment: 

Two Beakers, Hot and Cold Water, Food Coloring.

Procedure:

Place ice cube into 800 ml of water before hand to make the cold water bath.  Take out any remaining ice cubes before doing the demonstration.

Do not take the beaker with the hot water into the classroom until 5 minutes before doing the demonstration.

Place the beaker of hot water next to the beaker of cold water.  Place a drop of blue or green food coloring into the center of the surface of each.  Note that the drop in the hot water diffuses much faster than the drop in the cold water.   

References:

  • C. Booth, Tom Beer, and J. D. Penrose, "Diffusion of Salt in Tap Water", #5, May 1978, p. 525.
  • Bobby Mercer, Wiggle, Wiggle, Wiggle", Junk Drawer Chemistry, 2016, p. 181.

Video Credit: Jonathan M. Sullivan-Wood.

4D50.60 - Diffusion - Liquids - Cold = Left - Hot = Right