Ca
They are both capable of holding a maximum of 10
Electrons occupy orbitals in a definite sequence, filling orbitals with lower energies first. Generally, orbitals in a lower energy level have lower energies than those in a higher energy level. But, in the third level the energy ranges of the principal energy levels begin to overlap. As a result, the 4s sublevel is lower in energy than the 3d sublevel, so it fills first.
This alkali metal is Rubidium Rb, having atomic no 37
transition metals b/c some, such has iron, have an incomplete 3d sublevel as well as a complete 4s level that are used in reactions
The 3d sublevel is not filled until after the 4s sublevel, because the 3d sublevel has more energy than the 4s sublevel, and less energy than the 4p sublevel.
The 3d sublevel is not filled until after the 4s sublevel, because the 3d sublevel has more energy than the 4s sublevel, and less energy than the 4p sublevel.
The 3d sublevel is not filled until after the 4s sublevel, because the 3d sublevel has more energy than the 4s sublevel, and less energy than the 4p sublevel.
Be
Ca
Radium
They are both capable of holding a maximum of 10
Ca
Ca
Ca
Ca
Ca