The number of alkali metal(s), from Li, K, Cs, $Rb$ having ionization enthalpy greater than $400\, kJ$ $mol ^{-1}$ and forming stable super oxide is
The number of alkali metal(s), from Li, K, Cs, $Rb$ having ionization enthalpy greater than $400\, kJ$ $mol ^{-1}$ and forming stable super oxide is
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Correct Answer: 2
Solution and Explanation
K and Rb form stable superoxides, but Cs has an ionization enthalpy less than 400 kJ/mol.
Thus, the correct answer is 2, as K and Rb are the metals that meet the criteria.
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Concepts Used:
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