2 Energy LevelsElectrons surround the nucleus of an atom in regions called energy levels.
3 Periods on the Periodic Table Each period has a new electron energy levelPeriod 1 = 1 energy levelPeriod 2 = 2 energy levelsPeriod 3 = 3 energy levels
4 Atom modelsWhen drawing an atom, the nucleus (made of protons and neutrons) is in the center.Each energy level (filled with electrons) is a new circle around the nucleus.How many electrons are in this atom?Can you name the element?6 electrons, means it has 6 protonsIt is Carbon (atomic number 6)
5 Valence electrons - the number of electrons in the outermost shell How many valence electrons are in Si?4How many valence electrons are in Ge?4SiGe
6 Each group has the same number of. electrons in the outermost energy Each group has the same number of electrons in the outermost energy level. (valence electrons)
7 Valence electrons of elements on the periodic table
8 Summary of the Table’s arrangement Elements are arranged by increasing atomic numberElements in the same period have the same number of electron energy levelsElements in the same group the same number of valence electronsValence electrons are the electrons found in the outermost energy level.
9 Can you predict the electron arrangement just by looking at the element’s position on the table?