Answer:
See explanation
Explanation:
In writing the electron configuration of atoms, the core electrons are those electrons that occur in the inner shells. They do not participate in chemical reaction.
The valence electrons are those electrons that occur on the outermost shell of an atom and does participate in chemical reaction.
For Xe, the core electrons are; 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 4d10 while the valence electrons are; 5s25p6
For Ca, the core electrons are; 1s2 2s2 2p6 3s2 3p6 while the valence electrons are 4s2.
Hence, there are 18 core electrons and 2 valence electrons for Ca and 46 core electrons for Xe and 8 valence electrons
