On Earth, it is relatively rare—5.2 ppm by volume in the atmosphere. Most terrestrial helium present today is created by the natural radioactive decay of heavy radioactive elements …

氦气（Helium），稀有气体元素的一种，化学元素符号为He，原子序数2，原子量4.0026，是一种无色、无臭、无味、不可燃的单原子惰性气体，非金属元素，密度为0.1786kg/m3，熔点 …

Oct 24, 2025 · Helium, chemical element, inert gas of Group 18 (noble gases) of the periodic table. The second lightest element, helium is a colorless, odorless, and tasteless gas that …

Helium flips the traditional wireless infrastructure model and puts you in charge. The economic engine of this model is HNT, a cryptocurrency, which fuels the growth of the Helium Network …

It is a helium-neon based, one colour, three beam system, capable of measuring two components of velocity using light polarization for discrimination.

Element Helium (He), Group 18, Atomic Number 2, s-block, Mass 4.003. Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images.

Feb 22, 2023 · Helium element traces can be found in the environment, and the air we breathe contains around 0.000524% helium. The energy-producing fusion processes in stars produce …

Helium is an odorless, nontoxic, colorless, tasteless gas; it has a very low chemical reactivity and it is lighter than air. These characteristics are why helium plays a prominent role in space …

Chemical element, Helium, information from authoritative sources. Look up properties, history, uses, and more.

氦 ㄏㄞˋ （拉丁語： Helium，源於希臘語 ἥλιος 「太陽」；舊譯 氜）是一種 化學元素， 化學符號 為 He， 原子序數 為2， 原子量 為 4.002 602 u。 是一種無色、無臭、無味、無毒的惰性 單 …