A large amount of Helium was produced after the Big Bang. Some are formed in stars from the nuclear fusion of Hydrogen atoms, And some are produced as a result of radioactive decay from Heavier elements. It is the second most abundant element after Hydrogen in the observable universe. But it is very rare on Earth. Some 5.5 ppm by volume could be found in Earth's atmosphere. It is has been estimated that some 3000 metric tons per year are generated from radioactive decay in the lithosphere. The concentration is varying from 8 parts per billion to 4 parts per trillion in Earth's crust to seawater respectively.
How many valence electrons does helium have?
Helium has two electrons. It has an atomic number (Z) 2. Helium is in the first period of the periodic table and in group 18 of the noble gases. It has a stable electronic configuration of 1S2. This means there are two electrons in its s-orbital when in the ground state.
How is helium made?
Helium is produced naturally in the lithosphere from the radioactive decay of heavier elements like Uranium and thorium. Alpha particles produced during radioactive decay combine with electrons producing Helium atoms. Natural gas has some 5-7% of Helium but can be different from place to place. It is extracted and collected from Natural gas through fractional distillation. Helium has a very low boiling point so, it is collected first in the fractional distillation. The United States is producing some 78% of the total world production of Helium the rest is coming from Qatar, Algeria, Russia, and Poland, etc.
How many neutrons does helium have?
Helium has two neutrons. There are some 9 isotopes of Helium in which two are stable and naturally occurring isotopes. Helium-3 and Helium-4 are the two stable isotopes. Helium-3 has two protons and one neutron. Helium-4 has two protons and two neutrons. Helium-3 can be found in abundance 99.99%.