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Hydrogen and helium only need two valence electrons to achieve stability because they aim to fill their outer electron shell, which is the first shell that can accommodate a maximum of two electrons. Hydrogen has one electron and can bond with another hydrogen atom to complete its shell, while helium already has two electrons and is stable as is, fulfilling the criteria of the "duet rule" for these light elements. This contrasts with heavier elements that follow the octet rule, requiring eight electrons for stability.
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How many electrons are in the outer energy level of a helium atom?
Helium and hydrogen and group 3 to 12 got 2 valence electron
How many electrons would hydrogen need to have a full outer she?
Hydrogen has one electron in its outer shell and typically needs one more electron to achieve a full outer shell, which would complete its valence shell with two electrons (like helium). Therefore, hydrogen would need one additional electron to have a full outer shell.
Helium atoms only need how many valence electrons to have a filled outermost energy level?
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.
How many electrons do hydrogen and helium need to fill their outermost energy level?
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!!
Which electrons in the first period have higher ionization energies?
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.
Why does helium atom need only two valance electrons?
because it only has one orbital
Is it true that the octet rule acquires the valence electrons total?
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.
Which atom does not need 8 electrons in it outer energy level to be stable?
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.
How many valance electrons do most elements need to have a stable electron configuration?
8 valance electron
What makes a group not reactive on the periodic table?
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.
Is argon a reactive element?
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. ''
How many electrons are in the outer energy level of a helium atom?
Helium and hydrogen and group 3 to 12 got 2 valence electron
Does helium have a complete outer shell?
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.
What two atoms will have their outer energy level filled with two electrons?
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.
How many additional valence electrons does fluorine need to have a full valance shell?
1
How many electrons would hydrogen need to have a full outer she?
Hydrogen has one electron in its outer shell and typically needs one more electron to achieve a full outer shell, which would complete its valence shell with two electrons (like helium). Therefore, hydrogen would need one additional electron to have a full outer shell.
Helium atoms only need how many valence electrons to have a filled outermost energy level?
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.
