Period 6 element between barium and hafnium, and radium and rutherfordium, respectively. This convention is entirely a matter of aesthetics and formatting practicality; a rarely used wide-formatted periodic table inserts the lanthanide and actinide series in their proper places, as parts of the table's sixth and seventh rows (periods). Lanthanum is a chemical element with the symbol La and atomic number 57. It is the first element in the lanthanide series. It is a soft, ductile, silvery-white metal that tarnishes rapidly when exposed to air and is soft enough to be cut with a knife. It is the eponym of the lanthanide series,
Inorganic compounds by element Inorganic compounds by element This is a list of common inorganic and organometallic compounds of each element. Compounds are listed alphabetically by their chemical element name rather than by symbol, as in list of inorganic compounds. AcCl, AcF, AcO AlH, AlBr, AlBr, AlCl, AlCl(OH), AlF, AlGaAs, AlGaN, Al(OH), AlI, AlI, Al("i"-PrO), Al(NO), AlN, AlO, Al(SO), AlS, "i"-BuAlH (DIBAL-H), EtAlCl, LiAlH, (−Al(CH)O−), EtAl, MeAl AmCl, AmCl, AmF, AmO SbF, SbF, SbCl, SbCl, SbO, SbO, SbS, SbS, InSb, CHKOSb, KSbF, NaSbF, SbH, (CH)Sb HArF AsBr, AsCl, AsF, AsF, AsO, AsO, AsS, AsH, (CH)AsOOH, GaAs, KAsF, KHAsO, NaAsO, NaHAsO, NaAsO, (CH)As, (CH)As LiAt,