P3H4T1H4A1L1E1I1N1
17 points
PHTHALEIN is validvalid
[n PHTHALEINS]
any one of a very important class of dye-yielding materials formed by the union of phenols with phthalic anhydride [n -S]
[n PHTHALEINS]
any one of a very important class of dye-yielding materials formed by the union of phenols with phthalic anhydride [n -S]