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QJEEM06Ch1dbb: JEE Main 2006 Chemistry - Class 11 JEEM06Ch1dbb Solution: The increasing order of the first ionization enthalpies of the…

The increasing order of the first ionization enthalpies of the elements B, P, S and F (lowest first) is :

Multiple Choice Options

  • A F < S < P < B
  • B P < S < B < F
  • C B < P < S < F
  • D B < S < P < F

Step-by-Step Verified Solution

The correct order of ionisation enthalpies is F &gt; P &gt; S &gt; B

NOTE : On moving along a period ionization enthalpy increases from left to right and decreases from top to bottom in a group. But this trend breaks up in case of atom having fully or half filled stable orbitals.

In this case PP has a stable half filled electronic configuration hence its ionisation enthalpy is greater in comparison to S.S. For B(5) electronic configuration is = 1s22s22p1 and P(15) electronic configuration is = 1s22s22p63s23p3. As P has half filled valence shell so removing electron will be harder compare to B. Hence by checking all options the correct possible order is

B < S < P < F

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