A Manual of the Chemistry of the Carbon Compounds

424 THE CHEMI8TBY OF
above 300°, and subliming in soft, pale-yellow, interlaced needles.
Mitrio acid oxidizes it to diphthalio acid (C^A,(CO),(CO.OH)«
forming microscopic needles, metying at 265°. By heating this acid
above its melting-point, it yields diphthalyl, and phthalic anhydride,
whilst by boiling it with nitric acid for some time it ia oxidized to
phthalic acid.
C2(COH6)4.
By acting with phosphorus pentachloride on diphenyl ketone it is
converted into diphmyl-dicliiwomtham (C^Hj^CClj, and this compound,
when heated with silver-dust, yields tetraphenyl-etbene,
crystallizing from hot benzene in pointed prisms, melting at 221°.
Hot concentrated sulphuric acid converts it into tctrapltenyl-tetramdphonic
acid, which, when fused with potash, yields the corresponding
phenol, or
Tetrmytelraplienyhetfane C^(C9H4.OH). crystallizing from hot
glacial acetic acid in very thin, small plates, which in tho air assume
a faint violet tinge. On adding ferric chloride to a solution
of this phenol in acetic acid, a dark blood-red liquid is formed,
from which crystals, having a metallic lustre, and consisting of
(