Copper(l1) Acetate Monohydrate-An
Erroneous Melting Point
The melting point of [ C U ( C ~ H Z O ~ ) ~ . H is Zgiven O ] ~ a t llSPC in volume I of the International Critieol Tables (p. 123), a value repeated in several handbooks (e.g., CRC Handbook of Chemistry and Physics, Longe'.~Handbook of Chemistry, and The Merck Index). We have observed, however, no physical change in the compound a t 115' in either an open or a sealed, evacuated capillary tube. A differential thermal analysis' showed only the loss of water a t about 14S0 and s series of complicated reactions at 245-450'. Our literature search has shown the probable source of this error. Angel and Hareourt2 reported that when this compound was heated under reduced pressure they observed the formation of liquid decomposition products, sometimes a t a temperature as law as 115". A German abstract of this p a p d said that when the compound was heated, ". . . a liquid forms a t about 115'. . ." (our translation). We believe that when melting m i n t data were beine collected for the I.C.T. this abstract. but not the orieinal was reviewed and the liauid was " ,oaoer. . .~~ ;hOllyht10 he m r ~ l r r ~ s n lSuch t . u misunderstanding could'nor occur with the o r ~ n a nor l u,ith the English angi French abitr:uts. The error iprrnd from the I C T , its appearance in the smaller hsndhuoks firllming rhe publicatim uf the I.C T volume by a t least four years.
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Hill, d. A,, Murphy, C. B., and Schacher, G. P., Anal. Chim. Acto. 24,496 (1961). 'Angel, A,, and Harcourt, A. V., J. Chem. Soe., 81,1385 (1902). Chem. Zent. 73-11,1407 (1902). Southern Illinois University Carbandale. 62901
R. F. Trimble Gaila Brawn
Volume 53,Number 6, June 1976 / 397
