- 0.10 g thymolphthalein for blue ink or phenolphthalein for red ink (1/3 of 1/8 tsp)
- 10 ml (2 tsp) ethyl alcohol (ethanol) [can substitute 14 ml or 3 tsp of ethyl rubbing alcohol]
- 90 ml water
- 20 drops of 3M sodium hydroxide solution or 10 drops 6M sodium hydroxide solution [make a 3 M sodium hydroxide solution by dissolving 12 g of sodium hydroxide NaOH (1 level tablespoon of lye) in 100 ml (1/2 cup) of water.]
Let's try it out...
