REED REI.ATION BETWEEN VAI-ENCE & ATOMIC AVEJGHT. 659 



ZIRCONIUM. 



Atomic weight about 92. 



Marignac's experiments, * the 

 most reliable with which I am ac- 

 quainted, give values for the atomic 

 weightofZr varying from less than 

 90 to more than 92. The higher 

 value seems most likely to prove 

 correct, though 90 is generally ac- 

 cepted. 



Zr is -I-4 in 



ZrOi and all zirconium salts, 

 NagZrOg and all zirconates, 

 K.,ZrF,. and all zircono-fluorides. 



COLUMBIUM. 



Atomic weight 94(?). 

 C^ is +5 in 

 C^^O-,, columbium pentoxide. 



NIOBIU.VI. 



Atomic weight 94.! 

 N^ is -j- 2 in 

 N^,0,, niobium dioxide. 



M03C/4BA-0, molybdenum chloro- 

 bromide. 



NbCl, 



N3 is +3 in 

 niobium trichloride. 



Ni5 is 4- 4 in 

 Nj^jO^' niobium tetroxide. 



X^ is 4" 5 in 

 N^jOj and all niobates, 

 N^C/5, niobium pentachloride, 

 N^Br,, " pentabromide. 

 NAF,, " pentafluoride, 



N5OF3, niobyl fluoride, 

 NiOC/g, " chloride, 

 NiOBrj, " bromide. 



MOLYBDENUM. 



Atomic weight 96.009. J 

 Mo is 4- 2 in 

 MoO, molybdenum monoxide, 

 M0CI2, " dichloride, 



M0B/-2, " dibromide, 



Mo3C/4COH)2, " chloro- hydrate 



MogBy^COH),, 



Mo,Bi\^F2, 

 Mo,Br,SO^, 



bromo- hydrate, 

 bromo- chloride, 

 bromo-fluoride, 

 bromo-sulphate. 



Mo is -j- 3 in 

 Mo.O-^, molybdenum sesquioxide, 

 MooC/,., " sesquichloride, 



Mo2Br,., '• sesquibromide,. 



MoP, " phosphide. 



Mo is -|- 4 in 

 M0O2, molybdenum peroxide, 



RHODIUM. 



Atomic weight about 104. 



R// is + 2 in 

 R//0, rhodium monoxide, 

 R>iS, " monosulphide. 



R/i is +3 in 

 R//2O3 and all rhodic salts. 



R/i is + 4 in 

 RyiOz, rhodium dioxide, 

 R;/(0H)4, " tetrahydrate. 



RUTHENIUM. 



Atomic weight about 104. 

 Ru is -|- 2 in 

 RmO, ruthenium monoxide, 



* Ann. Chem. Phys. (3), 60, 270, i860. f Ann. C/ieni, Phys. (4), viii., 16. 



I = 16, Rammelsberg, Berlin Monatsbericht, 1877, 574. Dumas, Ann. Chem. Phar 

 105,84 and 113, 23. Mo = 95, 92. 



iv._4— 8 [J"ly ^7, 18S6. 



