resorcinolphthalein
n 1: a yellow dye that is visible even when highly diluted; used
as an absorption indicator when silver nitrate solution is
added to sodium chloride in order to precipitate silver
chloride (turns pink when no chloride ions are left in
solution and negative fluorescein ions are then absorbed)
[syn: {fluorescein}, {fluoresceine}, {fluorescent dye},
{resorcinolphthalein}]