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Lanthanide oxides: clockwise from top center: praseodymium, cerium, lanthanum, neodymium, samarium and gadolinium. The chemistry of the lanthanides is dominated by the +3 oxidation state, and in Ln III compounds the 6s electrons and (usually) one 4f electron are lost and the ions have the configuration [Xe]4f (n−1). [23]
Lanthanide metals react exothermically with hydrogen to form LnH 2, dihydrides. [1] With the exception of Eu and Yb, which resemble the Ba and Ca hydrides (non-conducting, transparent salt-like compounds),they form black pyrophoric, conducting compounds [6] where the metal sub-lattice is face centred cubic and the H atoms occupy tetrahedral sites. [1]
A mnemonic is a memory aid used to improve long-term memory and make the process of consolidation easier. Many chemistry aspects, rules, names of compounds, sequences of elements, their reactivity, etc., can be easily and efficiently memorized with the help of mnemonics.
Polyatomic anions made up of different elements are named either substitutively or additively, the name endings are -ide and -ate respectively e.g. : GeH 3 − germanide (substitutive), or trihydridogermanate(1−) (additive) TeH 3 − tellanuide substitutive where -uide specifies anion composed of additional hydride attached to parent hydride
The ending ‘ide’ normally indicates a negative ion, and therefore lanthanoid and actinoid are preferred to lanthanide and actinide." The last sentence is not an observation scanning thousands of chemistry articles, it is a normative recommendation.
The lanthanide and actinide elements (the f-block) are called inner transition metals and are sometimes considered to be transition metals as well. Since they are metals, they are lustrous and have good electrical and thermal conductivity.
The lanthanides are the 15 rare-earth chemical elements which lie between lanthanum and lutetium on the periodic table. The lanthanides are trivalent metals.
A period 6 element is one of the chemical elements in the sixth row (or period) of the periodic table of the chemical elements, including the lanthanides.The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical behaviour begins to repeat, meaning that elements ...