Verified Solution • 2025–26 Session
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QJEEM21Ch5f2f: JEE Main 2021 Chemistry - Class 11 JEEM21Ch5f2f Solution: Consider the elements Mg, Al, S, P and Si, the correct…
Consider the elements Mg, Al, S, P and Si, the correct increasing order of their first ionization enthalpy is :
Multiple Choice Options
- A Al < Mg < Si < S < P
- B Al < Mg < S < Si < P
- C Mg < Al < Si < S < P
- D Mg < Al < Si < P < S
Step-by-Step Verified Solution
On moving left to right in a period of the periodic table, Ionisation energy (I.E.) increases due to increase in effective nuclear charge i.e. Zeff.
But due to extra stability of fully filled and half-filled electronic configuration of Mg and P required ionisation enthalpy is more from neighbouring elements.
i.e. First ionisation enthalpy order is Al < Mg < Si < S < P.