PYQSide ExamsMy practice

Classification of Elements and Periodicity in Properties · Question 7

JEE Main 2026 (Online) 4th April Evening ShiftMCQEasy📈 Topic in 42% papers+4−1
1

The 1st ionization enthalpy for Mg is +737 kJ/mol. The most probable estimated value of the 2nd ionization enthalpy of Mg is .

  1. −906 kJ/mol
  2. −856 kJ/mol
  3. +1450 kJ/mol
  4. +590 kJ/mol

Answer

(3) +1450 kJ/mol

Solution

Energy is always absorbed to remove an electron ⇒ ionisation enthalpy is positive ⇒ (1) and (2) are ruled out.

The 2nd electron is removed from Mg+, a positive ion: the remaining electrons feel a larger effective nuclear charge

⇒ iH2 > iH1 (= 737 kJ/mol) ⇒ (4), +590 kJ/mol, is ruled out.

Mg+ ([Ne] 3s1) still loses a valence 3s electron, so iH2 is roughly double iH1 (actual value ≈ 1450 kJ/mol).

Answer: (3)

JEE Main 2026 (Online) 4th April Evening Shift

Keep practising — Classification of Elements and Periodicity in Properties

2

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below :

  1. Both Statement I and Statement II are true
  2. Both Statement I and Statement II are false
  3. Statement I is true but Statement II is false
  4. Statement I is false but Statement II is true
JEE Main 2026 (Online) 2nd April Morning Shift
3

The correct set that contains all kinds (basic, acidic, amphoteric and neutral) of oxides is :

  1. Na2O, K2O, Al2O3 and As2O3
  2. Al2O3, As2O3, CO and NO
  3. K2O, Cl2O7, As2O3 and NO
  4. Na2O, N2O, Al2O3 and CO
JEE Main 2026 (Online) 2nd April Evening Shift
4

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below :

  1. Both Statement I and Statement II are true
  2. Both Statement I and Statement II are false
  3. Statement I is true but Statement II is false
  4. Statement I is false but Statement II is true
JEE Main 2026 (Online) 2nd April Evening Shift
5

In period 4 of the periodic table, the elements with highest and lowest atomic radii are respectively.

  1. Rb & Br
  2. Na & Cl
  3. K & Br
  4. K & Se
JEE Main 2026 (Online) 28th January Morning Shift
6

Consider the elements N, P, O, S, Cl and F. The number of valence electrons present in the elements with most and least metallic character from the above list is respectively.

  1. 7 and 5
  2. 6 and 7
  3. 5 and 7
  4. 5 and 6
JEE Main 2026 (Online) 28th January Evening Shift
7

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below

  1. Both Statement I and Statement II are false
  2. Statement I is false but Statement II is true
  3. Statement I is true but Statement II is false
  4. Both Statement I and Statement II are true
JEE Main 2026 (Online) 24th January Morning Shift
8

The correct order of C, N, O and F in terms of second ionisation potential is

  1. C < N < F < O
  2. C < F < N < O
  3. F < N < C < O
  4. C < O < N < F
JEE Main 2026 (Online) 24th January Evening Shift
9

The correct trend in the first ionization enthalpies of the elements in the 3rd period of periodic table is :

  1. Si < S < Al < P < Cl
  2. Al < Si < S < P < Cl
  3. S < Si < Al < P < Cl
  4. Al < S < P < Si < Cl
JEE Main 2026 (Online) 23rd January Morning Shift
10

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below :

  1. Statement I is true but Statement II is false
  2. Statement I is false but Statement II is true
  3. Both Statement I and Statement II are true
  4. Both Statement I and Statement II are false
JEE Main 2026 (Online) 23rd January Evening Shift
11

A 'p'-block element (E) and hydrogen form a binary cation (EHx)+, while EH3 on treatment with K2HgI4 in alkaline medium gives a precipitate of basic mercury(II) amido-iodine. Given below are first ionisation enthalpy values ( kJ mol-1) for first element each from group 13, 14, 15 and 16. Identify the correct first ionisation enthalpy value for element E.

  1. 1402
  2. 1086
  3. 801
  4. 1312
JEE Main 2026 (Online) 22nd January Morning Shift

All Classification of Elements and Periodicity in Properties PYQs →

PDFDownload Classification of Elements and Periodicity in Properties PYQs as PDF Free, with answer key and a QR code to every solution — print it or study offline⬇
All JEE Main Chemistry chapters
Physical ChemistrySome Basic Concepts of ChemistryStructure of AtomStates of MatterThermodynamicsEquilibriumRedox ReactionsSolutionsElectrochemistryChemical Kinetics
Inorganic ChemistryClassification of Elements and Periodicity in PropertiesChemical Bonding and Molecular Structurep-Block Elements (Group 13 & 14)p-Block Elements (Group 15–18)d- and f-Block ElementsCoordination Compounds
Organic ChemistryOrganic Chemistry – Some Basic Principles and TechniquesIsomerismHydrocarbonsHaloalkanes and HaloarenesAlcohols, Phenols and EthersAldehydes, Ketones and Carboxylic AcidsAminesBiomoleculesPrinciples Related to Practical Chemistry