125 XI.-The Xelting artd Boiling Points of certain Inorganic Substcmces. By T. CARNELLEY D.Sc. Professor of Chemistry Firth College, Sheffield and W. CARLETON- WILLIAMS Assistant Lecturer on Chemistry 0 wens College. THE melting points of the following substances were determined by the specific heat method which has been previously described by one of us (this Journal 1876 1 489 and 1878 Trans. 273). Substance. Tellurium . . 'Tellurium TeClz TeCl TeBrz TeBr4 i i i i CuzBrz RbBC03 I cscl * * * * * . I { NaBrOB KC104 KI03 { i KIO4 Bi13 . M. p. 0 479 452 213 --371 1 379 389 J 494" 502 515 I 830i 836 845 J 626 1 632 634 J 379 I 383 J %1 :; 1 559 1 561 570 I 586 590 1 -Mean. 0 455 { 452 209 224 (corr.; about 280" 380 504 837 631 381 610 560 582 below 439" Remarks.- -A pure sample obtained from Tromms-dorf. This specimen was purified by Mr. L. Wills (this Journal 1879 Trans. 704) by dis-tillation in hydrogen &c. and was used by him in determining the atomic weight of the element. Measured by a thermometer. Prepared by dissolving cuprous oxide in hydrobromic acid. A determination of the copper in this specimen agreed with the calculated result. Prepared by ignition of the acid tartrate, From pure cesium alum. This salt undergoes partial decomposition, This salt decrepitates at 389" and melts at Decomposes with evolution of iodine; the In sealed capil-iodine being evolved. 582". residue melts a t 462".lary tubes the salt melts below 439'. TOL. XXXVII 126 CARNELLEY AND CARLETON-WILLIAMS { Lead iodide The following melting points were det,ermined by suddenly plunging sealed capillary tubes containing the salts into a zinc chloride bath at different temperatures and observing whether fusion took place :-Prepared by passing chlorine 019 bromine over a mixture of charcoal and beryllia. Begins to sublime below 100". BeCl, 585-617" BeBr? 585 -61 7 } Pe2CI6 306-307 Cr2Cl decomposes with liberation of chlorine but does not melt. The boiling points of several metallic salts were determined by the method which has been previously described by us in this Journal (1878 Trans. 281 and 18'79 Trans. 563). In t.he following table Column I contains the name of the substance 11 the salts used in measuring the boiling point the symbol + being used to indicate that the salt melts and - to show that it has not fused.I11 gives the melting points of these salts and I V the boiling point of the snb-stance. I. 11. --+ NaaS04 - c u f Ag + NaaS04 - cu - Ag + KCl + MOO - NaCl - Na2CO3 + Pb(P03)Z + PbZPzO - BaBr - Na2C03 + Li2C03 + NaBr - CaC1, - KC1 Na2C03 Na,SO, - Ag -111. IT. -0 (9561032) (86 1-954) (759-772) (806-812) (708-719) (861-954) 339 Remarks. From Trommsdorf. (Prepared by passing SO2 through B solution of I CuSO4 and KBr; also by dissolving cuprous oxide in hydrobromic acid. Analysis gave 44.20 per cent. Cu calculated 4425. Prepared by precipitating CuSO4 with KI in pre- i sence of sulphurous acid.I Decomposes with evolu- i tion of iodine. Prepared by the action of bromine on cadmium in the presence of alcohol. Prepared by dissolving me-tallic cadmium in hydri-odic acid. Prepared by dissolving pure lead in hydriodic acid. i Slowly decomposes on I boiling with liberation of t iodine. Measured by a thermometer. { The melting points of silver and copper have recently been redeter ON THE MELTING AND BOILING POINTS ETC. 127 mined by Violle (Compt. rend. Oct. 27th 1879) and we have made use of his numbers in the preceding experiments. The adoption of these numbers involves an alteration in our last paper (Chem. Xoc. Trans. 1879) viz. the substitution of 861-9.54" for 861-1000" as the temperature at which lead chloride cadmium chlo-ride and metallic sodium boil.The melting points of four of the above compounds were calculated by the method recently described by one of us (Proc. Boy. SOC. 1879, No. 197). The calculated numbers agree fairly well with the experi-mental results as is seen from the following data:-CsCl below 959" 904" Cu,Br . 7S2 777 BeCl 820-8 70 858-890 BeBr 802-820 858-890 Calculated. Observed. In our last communication (Chem. Xoc. Trans. 18723 565) we drew aftention to the fact that our determinations of the temperature of the boiling points of antimony tin bismuth and lead differed considerably from the boiling points of these metals as calculated by Wiebe's method (Bey. 12 788) and we now find that the observed boiling points of cadmium iodide and lead iodide by no means agree with the temperature calculated by means of Wiebe's formula. CdI 597" 708-719" PbI 547 861-954 Inconclusion we may point out a curious fact in connection with the melting and boiling points of the mercuric and cuprous halogen compounds vie. that in the mercuric compounds the melting point sinks and the boiling point rises with an increased molecular weight, whilst in the cuprous compounds the reverse is the case ; the melting point rises and the boiling point falls. Calculated. Observed. Chlorides. Bromides. Iodides. 244" 241" b. p. 303 319 349 m. p . 434 504 601 Mercuric. . Cuprous . . b. p. 954 861 76