Question

A Potassium (K) atom attains a stable electron configuration when it combines with.

one chlorine atom


two chlorine atoms


one calcium atom


two calcium atoms

Answer 1

Answer is: one chlorine atom.
They form ionic compound potassium-chloride (KCl).
Electron configuration of potassium: ₁₉K 1s²2s²2p⁶3s²3p⁶4s¹.
Electron configuration of chlorine: ₁₇Cl 1s²2s²2p⁶3s²3p⁵.
Potassium lose one electron to attains a stable electron configuration of noble gas argon (Ar).