2-3 spatulas of calcium hydroxide in a 500ml stock bottle and make up with distilled water.  Mix well, then allow the solids to settle.  If desired solids can be filtered off, but this is not necessary. Limewater is saturated calcium hydroxide Ca(OH)2. Add (solid) calcium hydroxide to water until no more will dissolve. Let it […]

The following web site has information on the use of luminol for blood detection, plus suggestions for replacing blood with potassium ferricyanide or other chemicals:http://chemistry.about.com/od/glowinthedarkprojects/a/luminolblood.htmApparently it works well but fades much faster than with real blood.