Chemistry - PERIODIC TABLE Question with Solution | TestHub

ns² → stable filled s-subshell → 1400 kJ mol⁻¹ → (D)

ns²np¹ → easy electron removal → 1200 kJ mol⁻¹ → (C)

ns²np³ → half-filled stable → higher IE → 1500 kJ mol⁻¹ → (B)

ns²np⁶ → noble gas (fully filled) → very high IE → 4000 kJ mol⁻¹ → (A)