If all of the elements in a group were the same, they would be the same element and wouldn't be in groups. You are slightly mislead; the elements in the groups are similar, not the same.
correct up above... each element has a different amount of protons changing its elemental properties. they are only catagorized in the same group because they have the same amount of valence electrons
extra info: the mass of the element atom is based on the weight of the Protons and Neutrons together only, not the electrons. This is because the exact mass of an electron is not yet fully known because they move so fast in the outer shell. it is estimated to be very very very small though, and due to this, the mass wouldn't change any if the electrons were added in or not... so there ya go buddy :)
group
Elements in the same group have similar physical and chemical properties.
The elements in a group do not have the same number of shells, however, the elements in a horizontal row do have the same number of shells.
No, they do not. However, elements in the same group have the same number of valence electrons.
All elements in the same group have the same number of valence electrons.
elements are in the same group since they react similarly to other elements in that group.
group
elements that share the same colum
Elements in group have same number of valence electrons. They also have same chemical properties.
Same elements of group have same valency. They possess same chemical behaviour.
Elements in the same group have similar physical and chemical properties.
No. Elements in the same group have same number of valence electrons.
The elements in a group do not have the same number of shells, however, the elements in a horizontal row do have the same number of shells.
No, they do not. However, elements in the same group have the same number of valence electrons.
Elements in the same group have similar properties as they have the same number of valence electrons.
Elements that have similar chemical properties occupy the same group on the Periodic Table.
Elements of same group have the same number of valence electrons and hence have similar properties.