Here's why:
* Calcium (Ca) is in group 2 of the periodic table, meaning it has 2 valence electrons (electrons in its outermost shell). It tends to lose these 2 electrons to achieve a stable electron configuration.
* Chlorine (Cl) is in group 17 of the periodic table, meaning it has 7 valence electrons. It tends to gain one electron to achieve a stable electron configuration.
To form a stable compound, one calcium atom loses its two valence electrons, and two chlorine atoms each gain one electron. This results in:
* Calcium forming a +2 ion (Ca²⁺)
* Chlorine forming two -1 ions (2Cl⁻)
The charges balance out, forming the compound CaCl₂.
The bond between calcium and chlorine is an ionic bond. This is because one atom (calcium) loses electrons to become positively charged, while the other atom (chlorine) gains electrons to become negatively charged. The opposite charges attract each other, forming a strong electrostatic attraction known as an ionic bond.
