The naturally-occurring group 8 elements (helium, neon, argon, and kyrpton) are not completely inert, but they are more nearly so than any other group.
=NOBLE GASES=
Valence shells mean that the outermost orbits of electrons are full. Recall that from the inside out, the number of electrons for a shell to be full are: 2, 8, 8, 8, etc... So, Helium, He (2) has a filled shell. Neon (10) has a filled inner shell (2) and a filled outer shell (8): 2 + 8 = 10. Argon (18) has a filled inner shell (2), another filled shell (8), and a valent shell (8): 2 + 8 + 8 = 18. The family is composed of the non-reative Noble Gases.
Astatine wouldn't form salt as readily as other elements in Group 17. Astatine is a radioactive metalloid. Other elements in Group 17 are nonmetals.
In Periodic table , Group 18 corresponds to Nobel gas group. They are six elements in this group. Helium , Neon , Argon , Krypton , Xenon , Radon constitute these group. They are chemically inert elements and having stable configuration.
Group 4 elements on the periodic table contain no period 2 elements whatsoever.
Elements in group 8 all have 8 valence electrons, this is why these elements are in group 8, they are called noble gases, some examples are Argon, Xenon,
group 8, the noble gasses.
Group 19 elements have 8 valence electrons (obey octet rule) and are hence stable.
The valency of first four main group elements is equal to their group numbers but elements from Group 5 to 8 have two valencies one equal to group number and second is obtained by subtracting group number from 8.
There are 8 elements in the third period of periodic table. The elements belong to group-1,2,13,14,15,16,17 and 18
They don't have one. Group 8 is noble gasses.
=NOBLE GASES=
That depends on the element in question. Atoms can have anywhere from 1 to 8 valence electrons. For the main group elements, Groups 1,2,13-18, the number of valence electrons are the number in the one's place in their group number, as follows: Group 1 Elements: 1 valence electron Group 2 Elements: 2 valence electrons Group 13 Elements: 3 valence electrons Group 14 Elements: 4 valence electrons Group 15 Elements: 5 valence electrons Group 16 Elements: 6 valence electrons Group 17 Elements: 7 valence electrons Group 18 Elements: 8 valence electrons The transition metals, Groups 3 - 12, are more complicated because they are adding d electrons, some of which behave like valence electrons, and many transition metals can have different numbers of valence electrons. For example manganese can have anywhere from 2 to 7 valence electrons.
group 7 - halogens group 8 - noble gases
Halogens these are the salt forming elements which are highly reactive
Neon - one of the stable and unreactive elements of group 8.
Both terms are acceptable due to the fact that eight electrons exist in the outermost shell of all elements in the group. Therefore, one could say that this group has 8 electrons in the outermost shell or that there are no electrons in the outermost shell - as the structure is stable! It is the perspective of a person.