Calcium has 2 valence electrons. This is because it is in Group 2 of the periodic table, and elements in this group have two electrons in their outermost shell. Specifically, calcium's valence electrons are in the 4s orbital, with an electron configuration ending in 4s²
. To summarize:
- Calcium's atomic number is 20, meaning it has 20 electrons.
- Its electron configuration is 1s22s22p63s23p64s21s^22s^22p^63s^23p^64s^21s22s22p63s23p64s2.
- The valence electrons are the two electrons in the 4s orbital, which are the outermost and highest energy electrons.
- When calcium forms ions, it typically loses these 2 valence electrons to achieve a stable electron configuration similar to argon
Therefore, calcium has 2 valence electrons.
