Indeed, is scary how Chinatsu can play the role of murder nurse haha.
Also, please send help.. Just the fact that Kyoko is between Ayano and Yui makes me think that the author did it on purpose just for teasing... My shipping is driving me crazy
Red solution : Probably phenol red in high basic solution
Blue solution : Copper sulfate
Yellow solution : Dichromate
Magenta ? solution : possibly Quinoneimine or Phenolphthalein in a basic solution