helium
n. inert gaseous element | ||||
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Helium Definition from Language, Idioms & Slang Dictionaries & Glossaries
| Webster's Revised Unabridged Dictionary (1913) |
Helium
(n.)
A gaseous element found in the atmospheres of the sun and earth and in some rare minerals.
(n.)
A gaseous element found in the atmospheres of the sun and earth and in some rare minerals.
| WordNet 2.0 |
helium
Noun
1. a very light colorless element that is one of the six inert gasses; the most difficult gas to liquefy; occurs in economically extractable amounts in certain natural gases (as those found in Texas and Kansas)
(synonym) He, atomic number 2
(hypernym) chemical element, element
Noun
1. a very light colorless element that is one of the six inert gasses; the most difficult gas to liquefy; occurs in economically extractable amounts in certain natural gases (as those found in Texas and Kansas)
(synonym) He, atomic number 2
(hypernym) chemical element, element
Helium Definition from Science & Technology Dictionaries & Glossaries
| Mineralogy Database |
Helium (He)
Atomic Mass : 4.002602
Atomic Number : 2
Name Origins: Greek, helios = "sun."
Year Discovered : 1895
Discovery Credits : Isolated in 1895 by Sir William Ramsay at London, UK, and independently by P. T. Cleve and N. A. Langlet at Uppsala, Sweden.
More Details
Atomic Mass : 4.002602
Atomic Number : 2
Name Origins: Greek, helios = "sun."
Year Discovered : 1895
Discovery Credits : Isolated in 1895 by Sir William Ramsay at London, UK, and independently by P. T. Cleve and N. A. Langlet at Uppsala, Sweden.
More Details
| ASTRONOMY UNBOUND |
Helium
The second element in the periodic table; it was discovered in the sun (hence its name) by Norman Lockyer studying the spectral lines. The atom is characterised by possessing two protonsin its nucleus. Usually there two neutronsas well. This abundant form of helium is about four times as heavy as hydrogen. Helium accounts for just under one quarter of the atomic matter in the universe and was principally formed during the first few minutes after the big bang. The isotope, helium-3 very short lived with only 1 neutron, is also important in nucleosynthesis (of elements). Helium is also produced by the nuclear fusion which takes place at the centre of stars on the main sequence.
| Chemistry of the Elements |
Helium
Name: helium
Symbol: He
Atomic number: 2
Atomic weight: 4.002602 (2) g r
Group in periodic table: 18
Group name: Noble gas
Period in periodic table: 1
Block in periodic table: p-block
CAS registry ID: 7440-59-7
Helium is one of the so-called noble gases. Helium gas is unreactive, colourless, and odourless. Helium is available in pressurised tanks.
Elemental helium is a colourless odourless monoatomic gas. Helium is the second most abundant element in the universe after hydrogen. a particles are doubly ionised helium atoms, He2+.
Helium is used in lighter than air balloons and while heavier than hydrogen, is far safer since helium does not burn. Speaking after breathing an atmosphere rich in helium results in a squeaky voice (don't try it!).
Name: helium
Symbol: He
Atomic number: 2
Atomic weight: 4.002602 (2) g r
Group in periodic table: 18
Group name: Noble gas
Period in periodic table: 1
Block in periodic table: p-block
CAS registry ID: 7440-59-7
Helium is one of the so-called noble gases. Helium gas is unreactive, colourless, and odourless. Helium is available in pressurised tanks.
Elemental helium is a colourless odourless monoatomic gas. Helium is the second most abundant element in the universe after hydrogen. a particles are doubly ionised helium atoms, He2+.
Helium is used in lighter than air balloons and while heavier than hydrogen, is far safer since helium does not burn. Speaking after breathing an atmosphere rich in helium results in a squeaky voice (don't try it!).
| General Chemistry Glossary |
helium (He)
Element 2, atomic weight 4.0026. A colorless, odorless, inert gas, first discovered in the emission spectrum of the sun in 1868.
Element 2, atomic weight 4.0026. A colorless, odorless, inert gas, first discovered in the emission spectrum of the sun in 1868.
Helium Definition from Entertainment & Music Dictionaries & Glossaries
| English to Federation-Standard Golic Vulcan |
Helium
tahal-tukh
tahal-tukh
Helium Definition from Sports Dictionaries & Glossaries
| Scuba Diving |
Helium
Second lightest gas; does not cause problems of narcosis seen with nitrogen, and is therefore used for very deep diving.
Second lightest gas; does not cause problems of narcosis seen with nitrogen, and is therefore used for very deep diving.
Helium Definition from Religion & Spirituality Dictionaries & Glossaries
| Webart Magic Astronomical Glossary |
Helium
he second lightest and second most abundant element. The typical helium atom consists of a nucleus of two protons and two neutrons surrounded by two electrons. Helium was first discovered in our Sun. Roughly 25 percent of our Sun is helium.
he second lightest and second most abundant element. The typical helium atom consists of a nucleus of two protons and two neutrons surrounded by two electrons. Helium was first discovered in our Sun. Roughly 25 percent of our Sun is helium.
Helium Definition from Encyclopedia Dictionaries & Glossaries
| Wikipedia English - The Free Encyclopedia |
Helium
Helium (He) is a colorless, odorless, tasteless, non-toxic, inert monatomic chemical element that heads the noble gas series in the periodic table and whose atomic number is 2. Its boiling and melting points are the lowest among the elements and it exists only as a gas except in extreme conditions. Extreme conditions are also needed to create the small handful of helium compounds, that are all unstable at standard temperature and pressure. It has a second, rare, stable isotope which is called helium-3. The behavior of liquid helium-4's two fluid phases, helium I and helium II, is important to researchers studying quantum mechanics (in particular the phenomenon of superfluidity) and to those looking at the effects that temperatures near absolute zero have on matter (such as superconductivity).
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