Water Into Wine

A trick of biblical proportions.

 

 

 

Category - Chemicals & Reactions

Key Idea - Acids & Bases

 

Purpose - Can be used to demonstrate the centre of gravity. 
Nature -  Demonstration or Class Practical
Materials -  4 x 250 ml beakers, distilled water, phenolphthalein,  0.1 M & 3 M Sodium hydroxide, 1 M Hydrochloric acid
Method - 
  1. Half fill beaker 1 with distilled water and add 5 drops of phenolphthalein.
  2. Into beaker 2 place two drops of 0.1 M Sodium hydroxide
  3. Into beaker 3 place 2 drops of 1 M Hydrochloric acid.
  4. Into beaker 4 place 2 drops of 3 M Sodium hydroxide.
  5. Arrange the beakers in order, and pour the contents from one to the other in order.
  6. The colours should go from colourless, to light pink, to colourless, to very dark pink.
Safety - Safety considerations when using corrosive chemicals
Explanation - The indicator phenolphthalein is pink in basic solutions and colourless in acidic solutions.  The solutions have been arranged to increase in strength, cancelling out the last change in each case.
Notes - The idea is to have so few drops in beakers 2 to 4 that they look empty before pouring.  The specific molarity and chemicals used is not too important as long as the alternate basic, acidic, basic and increase in molarity each time.