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Yttrium is a chemical element; it has symbol Y and atomic number 39. ... [15] 89 Y has a mass number close to 90 and has 50 neutrons in its nucleus.
This is a list of chemical elements and their atomic properties, ordered by atomic number (Z).. Since valence electrons are not clearly defined for the d-block and f-block elements, there not being a clear point at which further ionisation becomes unprofitable, a purely formal definition as number of electrons in the outermost shell has been used.
Atomic number (Z): 39: Group: group 3: Period: period 5: Block d-block Electron configuration [] 4d 1 5sElectrons per shell: 2, 8, 18, 9, 2: Physical properties ...
Natural yttrium (39 Y) is composed of a single isotope yttrium-89. The most stable radioisotopes are 88 Y, which has a half-life of 106.6 days, and 91 Y, with a half-life of 58.51 days. All the other isotopes have half-lives of less than a day, except 87 Y, which has a half-life of 79.8 hours, and 90 Y, with 64 hours.
A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). [ 1 ] The definitive visualisation of all 118 elements is the periodic table of the elements , whose history along the principles of the periodic law was one of the founding ...
Increasing atomic numbers between light and heavy rare-earth elements and decreasing atomic radii throughout the series causes chemical variations. [28] Europium is exempt of this classification as it has two valence states: Eu 2+ and Eu 3+. [28] Yttrium is grouped as heavy rare-earth element due to chemical similarities. [29]
As noted by the 2021 IUPAC report, Sc-Y-Lu-Lr is the only form that simultaneously allows for the preservation of the sequence of atomic number, avoids splitting the d-block into "two highly uneven portions", and gives the blocks the correct widths quantum mechanics demands (2, 6, 10, and 14). [8]
Yttrium-90 is produced by the nuclear decay of strontium-90 which has a half-life of nearly 29 years and is a fission product of uranium used in nuclear reactors. As the strontium-90 decays, chemical high-purity separation is used to isolate the yttrium-90 before precipitation .