Question

Find the neutral atom in the periodic table which has the same number of electrons as $K^{+}$ and $C{l}^{-}$. What is this number?

Answer 1

Argon is a neutral atom in the periodic table and has the same number of electrons as $K^{+}$ and $C{l}^{-}$. The atomic number of argon is 18. It has 18 electrons. Potassium (K) has 19 electrons but because it loses one electron, it becomes $K^{+}$ and has 18 electrons. On the other hand, chlorine (Cl) has 17 electrons but because it gains one electron, it forms $C{l}^{-}$ and has 18 electrons.