JEE Main 2021ChemistryClassification of Elements and Periodicity in PropertiesEasyMCQ

JEE Main 2021Classification of Elements and Periodicity in Properties Question with Solution

JEE Main 2021 (26 Feb Shift 1)

Question

Match List-I with List-II.

  List-I
Electronic configuration of elements
  List-II
ΔiH in kJ mol-1
a 1s22s2 p 801
b 1s22s22p4 q 899
c 1s22s22p3 r 1314
d 1s22s22p1 s 1402

Choose the most appropriate answer from the options given below:

Choose an option

Show full solutionCorrect option: A
Correct answer
Aaq,br,cs,dp

Step-by-step explanation

(a) 1s22s2Be

(b) 1s22s22p4O

(c) 1s22s22p3N

(d) 1s22s22p1B

The ionization enthalpy order is B<Be<O<N

Be has more IE compared to B due to extra stability & N has more IE compared to oxygen due to extra stability Hence,

N1402 kJ mol-1

O1314 kJ mol-1

B801 kJ mol-1

Be899 kJ mol-1

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About this question

This is a previous-year question from JEE Main 2021, covering the Classification of Elements and Periodicity in Properties chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.