Definitions for helvetium
hel·vetium

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1. helvetium

   Astatine is a chemical element with the symbol At and atomic number 85. It is the rarest naturally occurring element in the Earth's crust, occurring only as the decay product of various heavier elements. All of astatine's isotopes are short-lived; the most stable is astatine-210, with a half-life of 8.1 hours. A sample of the pure element has never been assembled, because any macroscopic specimen would be immediately vaporized by the heat of its own radioactivity. The bulk properties of astatine are not known with certainty. Many of them have been estimated from the element's position on the periodic table as a heavier analog of iodine, and a member of the halogens (the group of elements including fluorine, chlorine, bromine, and iodine). However, astatine also falls roughly along the dividing line between metals and nonmetals, and some metallic behavior has also been observed and predicted for it. Astatine is likely to have a dark or lustrous appearance and may be a semiconductor or possibly a metal. Chemically, several anionic species of astatine are known and most of its compounds resemble those of iodine, but it also sometimes displays metallic characteristics and shows some similarities to silver. The first synthesis of the element was in 1940 by Dale R. Corson, Kenneth Ross MacKenzie, and Emilio G. Segrè at the University of California, Berkeley, who named it from the Ancient Greek ἄστατος (astatos) 'unstable'. Four isotopes of astatine were subsequently found to be naturally occurring, although much less than one gram is present at any given time in the Earth's crust. Neither the most stable isotope astatine-210, nor the medically useful astatine-211, occur naturally; they can only be produced synthetically, usually by bombarding bismuth-209 with alpha particles.

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1. Helvetium

   Helvetium was the suggested name of chemical element number 85, now known as astatine, given to it by the Swiss chemist Walter Minder. Walter Minder announced the discovery in 1940. He chose the name based on "Helvetia", the Latin name for Switzerland, to honor his country of birth. In the year 1942 he together with Alice Leigh-Smith announced a second time the discovery of element number 85. This time he proposed the name anglohelvetium to honor also England, the home of Alice Leigh-Smith. Later it was proven that in fact he had not discovered element 85.

How to pronounce helvetium?

1. Alex

   US English

   David

   US English

   Mark

   US English

   Daniel

   British

   Libby

   British

   Mia

   British

   Karen

   Australian

   Hayley

   Australian

   Natasha

   Australian

   Veena

   Indian

   Priya

   Indian

   Neerja

   Indian

   Zira

   US English

   Oliver

   British

   Wendy

   British

   Fred

   US English

   Tessa

   South African

How to say helvetium in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of helvetium in Chaldean Numerology is: 3

2. Pythagorean Numerology

   The numerical value of helvetium in Pythagorean Numerology is: 7

References

1. ^ Wikipedia
   https://en.wikipedia.org/wiki/Helvetium
2. ^ Wikidata
   https://www.wikidata.org/w/index.php?search=helvetium