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Here [Ne] refers to the core electrons which are the same as for the element neon (Ne), the last noble gas before phosphorus in the periodic table. The valence electrons (here 3s 2 3p 3) are written explicitly for all atoms. Electron configurations of elements beyond hassium (element 108) have never been measured; predictions are used below.
57 La 2-1 - 58 Ce 2 1 1 - 59 Pr 2 3-- 60 Nd 2 4-- 61 Pm 2 5-- 62 Sm 2 ... which are not the same as the electron configurations for the same atoms in chemical ...
Lanthanum is a chemical element with the symbol La and the atomic number 57. It is a soft , ductile , silvery-white metal that tarnishes slowly when exposed to air. It is the eponym of the lanthanide series, a group of 15 similar elements between lanthanum and lutetium in the periodic table , of which lanthanum is the first and the prototype.
Integrated circuits and certain other electronic components are put into protective packages to allow easy handling and assembly onto printed circuit boards and to protect the devices from damage. A very large number of package types exist.
Naturally occurring lanthanum (57 La) is composed of one stable (139 La) and one radioactive (138 La) isotope, with the stable isotope, 139 La, being the most abundant (99.91% natural abundance). There are 39 radioisotopes that have been characterized, with the most stable being 138 La, with a half-life of 1.03×10 11 years; 137 La, with a half ...
Malicious caller identification, introduced in 1992 as Call Trace, [1] also called malicious call trace or caller-activated malicious call trace, is activated by the vertical service code *57 ("star fifty-seven"), and is an upcharge fee subscription service offered by telephone company providers which, when dialed immediately after a malicious call, records metadata for police follow-up.
He named this village in honor of Edward Tiffin, first governor of Ohio and later a member of the United States Senate who had helped gain statehood for the Ohio Territory in 1803. [11] Tiffin was incorporated by an act of the Ohio Legislature on March 7, 1835. In March 1850, Fort Ball was absorbed by Tiffin. In 1824, with the establishment of ...
When dialing a telephone number, the area code may have to be preceded by a trunk prefix or national access code for domestic calls, and for international calls by the international access code and country code. Area codes are often quoted by including the national access code. For example, a number in London may be listed as 020 7946 0321.