Practice question

Given: Which of the following 3d series elements has the highest second ionization enthalpy? Formula: Copper (Cu, Z = 29) has the highest second ionization enthalpy (1958 kJ/mol) due to the stability of 3d^{10 after losing one 4s electron.. Substitution: Substituting given values into formula as per NCERT 2026-27 method. Calculation: Simplifying step by step with proper SI units like m/s², J kg⁻¹ K⁻¹, 10⁻⁵, A m⁻¹ etc. Final Result: The computed value matches expected outcome and confirms correct choice as per latest NCERT 2026-27.