The number of alkali metal(s), from Li, K, Cs, Rb having ionization enthalpy greater than 400 kJ mol — JEE Mains Chemistry Past Papers Chemistry Question

💡 Solution & Explanation

Metal Li Na K Rb Cs IE (KJ/mol) 496 403 The super oxide O2– ion is stable only in the presence of large cations K, Rb, Cs. K, Rb have IE1 > 400 kJ/mol.