Helium and hydrogen and group 3 to 12 got 2 valence electron
Helium atoms only need 2 valence electrons to have a filled outermost energy level because helium is in the first period of the periodic table and its outermost energy level can only hold a maximum of 2 electrons.
Helium already has a full valence shell. Because the first orbital holds two, and the second orbital holds eight...Helium is already filling the first shell with its two electrons, and it has no more electrons to spill into the second orbital, therefore it's one and only shell is full. Hydrogen tends to gain one electron in order to fill its outermost energy level. Hydrogen only has one, but it needs two to fill it's valence shell, so it will gain one. Long story short, helium is already full (that's why it's in the noble gas group) and hydrogen tends to gain one electron, and form a negative ion. No honey it has a number and that is 2 duh!!
The elements of the first period are hydrogen and helium. The trend for ionization energy is to increase left to right across the same period, so helium's ionization energy is higher. Which makes sense, because helium has a full 1s-level, meaning it doesn't need to react. Hydrogen, on the other hand, is very reactive, which is why we stick it in group 1.
Helium has 2 valence electrons and has completely filled orbitals / shells and helium is stable.
because it only has one orbital
Yes that is true for the first 20 elements, except helium and hydrogen which needs 2 valance electrons to be complete. After 20, things change, but we don't need to worry about it at the basic level.
Hydrogen is an atom that does not need 8 electrons in its outer energy level to be stable. Hydrogen only needs 2 electrons to fill its outer energy level.
8 valance electron
A full octet, valance shell. A valance shell with eight electrons, such as the Nobel gases have, doe not need to donate or accept electrons into or out of the valance shell to be stable.
Not really. Argon is a Nobel gas with a full valance octet; 8 valance electrons that do not need to accept or donate electrons to be '' happy. ''
Helium and hydrogen and group 3 to 12 got 2 valence electron
Helium and neon will have their outer energy level filled with two electrons. Helium has 2 electrons in its only energy level, while neon has 8 electrons in its second energy level.
Not by itself, no (that is, hydrogen is not a noble gas). A neutral hydrogen atom starts out with 1 electron, but it needs 2 electrons to fill its shell. Therefore, a hydrogen atom will often form 1 covalent bond with another atom, in order to gain that 1 extra electron it needs to fill its shell. Important note: Most elements need 8 electrons to get a full shell, but hydrogen is the exception: it only needs 2 electrons to get a full shell.
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Helium atoms only need 2 valence electrons to have a filled outermost energy level because helium is in the first period of the periodic table and its outermost energy level can only hold a maximum of 2 electrons.
Helium ions can be synthesized by removing electrons from a helium atom and it would need a tremendous energy.