JEE Main202227 Jul 2022Morning ShiftChemistryClassification of Elements and Periodicity in PropertiesActual
The incorrect statement is
Options
- AThe first ionization enthalpy of K is less than that of Na and Li
- BXe does not have the lowest first ionization enthalpy in its group
- CThe first ionization enthalpy of element with atomic number 37 is lower than that of the element with atomic n
- DThe first ionization enthalpy of Ga is higher than that of the d-block element with atomic number 30 .
Correct answer
D. The first ionization enthalpy of Ga is higher than that of the d-block element with atomic number 30 .
Step-by-step solution
Ionisation enthalpy of alkali metals decreases down the group from Li to Cs. This is because of increase in size which outweighs the increasing nuclear charge, and the outermost electron is very well screened from the nuclear charge. Li > Na > K Due to stable electronic configuration noble gases exhibit very high ionisation enthalpy. However, it decreases down the group with increase in atomic size. He > Ne > Ar > Kr > Xe > Rn Alkaline earths have higher ionization enthalpy values than a