The outer shell contains just one electron on the left hand side of the table, but is filled by the time you get to the right hand side. Moving down each group, you can see that the number of electrons in the outermost shell is the same as the group number. read more
The outer shell contains just one electron on the left hand side of the table, but is filled by the time you get to the right hand side. Moving down each group, you can see that the number of electrons in the outermost shell is the same as the group number. Each element in a group therefore has the same number of electrons in its outer shell. read more
The number of energy levels increases as you go down the periodic table. In any given family, an atom with more electron shells than an atom with less will have less of a grip on it's electrons because both nuclei have relatively the same attraction. read more