The whole mass dissolves on heating, and the anthracene crystallizes out on cooling.
COC 6 H 6 CH Anthracene crystallizes in colourless monoclinic tables which show a fine blue fluorescence.
It crystallizes in prisms which melt at 36° C. and boil at 201 0.8 C. It is soluble in water, and the aqueous solution gives a blue coloration with ferric chloride.
The salt crystallizes out on cooling with 7 molecules of water, forming colourless orthorhombic prisms, usually small and needle-shaped.
This is generally effected by adding the calculated amount of potassium chloride (of which immense quantities are obtained as a by-product in the Stassfurt salt industry) dissolved in hot water to a saturated boiling solution of sodium nitrate; the common salt, which separates on boiling down the solution, is removed from the hot solution, and on cooling the potassium nitrate crystallizes out and is separated and dried.