group 7 - halogens group 8 - noble gases
all have 8 electrons in the valence shell
The number of valence electrons for the elements increases across a period, from 1 (group 1) to 8 (group 18).
The noble gases are found in Group 18 of the periodic table. These elements are known for their stability and reluctance to form chemical bonds with other elements due to their full outer electron shells.
These groups are groups 3 to 12 (transition metals) containing each four chemical elements.
Group 8 elements, also known as the noble gases, have 8 valence electrons. This is the maximum number of electrons that can occupy the outer shell of an atom, giving them stability and low reactivity.
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.
group 8, the noble gasses.
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.
group 7 - halogens group 8 - noble gases
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
=NOBLE GASES=
Elements in every group of the periodic table has some number of valence electrons. The exception is, when it comes to group 18, the number of valence electrons might be considered as either 0 or 8.
Halogens these are the salt forming elements which are highly reactive
Group 8A elements have 8 valence electrons. This means that the highest occupied energy level in Group 8A elements will have 8 electrons, as the maximum number of electrons in an energy level is 8 based on the octet rule.