Arjuna JEE Main (2026)
MANTHAN
Chemistry Periodic Classification
Exercise-1 8. The ionic radii of N3–, O2– and F– are respectively given by -
(a) 1.36, 1.40, 1.71 (b) 1.36, 1.71, 1.40
PERIODIC TABLE (c) 1.71, 1.40, 1.36 (d) 1.71, 1.36, 1.40
1. Three element X, Y, Z are following Doberiner’s Triad rule. 9. Arrange the following element in increasing order of atomic
If the atomic weight of X and Y are 10 and 26 respectively, radii:
then atomic weight of Z will be (a) Na < K < Mg < Rb (b) K < Na < Mg < Rb
(a) 34 (b) 40 (c) 42 (d) 18 (c) Mg < Na < K < Rb (d) Rb < K < Mg < Na
2. If Aufbau rule is not followed, K (Z = 19) will be placed in 10. Which of following is arranged in decreasing order of size?
________ block. (a) Mg2+ > Al3+ > O2– (b) O2– > Mg2+ > Al3+
(a) s (b) p (c) d (d) f 3+ 2+
(c) Al > Mg > O 2– (d) Al3+ > O2– > Mg2+
3. In the general electronic configuration - (n – 2)f 1–14 11. In which of the following compounds, manganese show
(n – 1)d0–1 ns2, if value of n = 7 the configuration belongs to maximum radius?
(a) Lanthanoides (b) Actinoides (a) MnO2 (b) KMnO4
(c) Transition elements (d) None of these (c) MnO (d) K3[Mn(CN)6]
4. Given atomic number 15, 33, 51 represents the following 12. The correct order of atomic size would be
family - (a) Ni < Pd Pt (b) Pd < Pt < Ni
(a) Carbon family (b) Nitrogen family (c) Pt > Ni > Pd (d) Pd > Pt > Ni
(c) Oxygen family (d) None of these 13. Choose incorrect option regarding atomic size.
Atomic Size, Zeff (a) Zr Hf (b) Fe Co Ni
(c) Y La (d) All of the above
5. Correct order of radius of iso-electronic species is: –
(a) Cl– < S2– < K+ < Ca2+ 14. If the ionic radii of K+ and F are nearly the same (i.e., 1.34 Å),
then the atomic radii of K and F respectively are:
(b) S2– < Cl– < K+ < Ca2+
(a) 1.34 Å, 1.34 Å (b) 0.72 Å, 1.96 Å
(c) Ca2+ < K+ < Cl– < S2–
(c) 1.96 Å, 0.72 Å (d) 1.96 Å, 1.34 Å
(d) K+ < Ca2+ < Cl– < S2–
15. In which of the following pairs, atomic size of second atom
6. Which of the following is generally true regarding effective
is larger than the first one?
nuclear charge (Zeff)?
(a) Br, Cl (b) Na, Mg
(a) It increases on moving from left to right in a period.
(c) Sr, Ca (d) N, P
(b) It remains almost constant on moving top to bottom in
a group. 16. Which of the following configuration of atom has largest
radius?
(c) For isoelectronic species, as Z increases, Zeff decreases.
(a) 1s22s22p63s2 (b) 1s22s22p63s23p1
(d) Both (a) and (b)
(c) 1s22s22p63s23p3 (d) 1s22s22p63s23p5
7. From the given set of species, point out the species from
17. The maximum tendency to form unipositive ion is for the
each set having highest Zeff.
–
element with the electronic configuration-
(I) O2–, F , Na+ (a) 1s22s22p63s2 (b) 1s22s22p63s23p1
(II) Li, Be, Na (c) 1s22s22p63s23p2 (d) 1s22s22p63s23p3
–
(III) He, Li+, H
18. If internuclear distance between Cl atoms in Cl 2 is
I II III 10 Å & between H atoms in H2 is 2 Å, then calculate
(a) Na + Be Li+ internuclear distance between H & Cl (Electronegativity of
–
(b) O2– Li H H = 2.1 & Cl = 3.0).
–
(c) F Na He (a) 5.919 Å (b) 6.9 Å
(d) Na+ Be He (c) 7.919 Å (d) 4.91 Å
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, 19. Which of the following is increasing order of paramagnetism? 29. Correct order of electron affinity is:
(a) Al < Mg < O < N (b) Mg < Al < N < O (a) S > P (b) S < P
(c) Mg < Al < O < N (d) N < O < Al < Mg (c) N > P (d) O > S
Ionisation Energy (Ionisation Enthalpy) 30. Among O, O+, O2+ and O2–, the species having most positive
20. Which of the following element has highest ionisation and most negative value of ΔHeg are, respectively
energy? (a) O+ and O (b) O2+ and O2–
(a) Oxygen (b) Nitrogen (c) O and O2– (d) O2– and O2+
(c) Fluorine (d) Helium 31. Of the following elements, which possess the highest electron
21. The correct order of stability of Al+, Al2+, Al3+ is- affinity?
(a) Al3+ > Al2+ > Al+ (b) Al2+ > Al3+ > Al+ (a) As (b) O
(c) Al2+ < Al+ > Al3+ (d) Al3+ > Al+ > Al2+ (c) S (d) Se
22. IP1 and IP2 of Mg are 178 and 348 Kcal mol–1. The enthalpy 32. Increasing order of electron affinity for the following
required for the reaction, Mg → Mg2+ + 2e– is configuration.
(a) + 170 Kcal (b) + 526 Kcal A. 1s22s22p3 B. 1s22s22p4
(c) – 170 Kcal (d) – 526 Kcal C. 1s22s22p63s23p3 D. 1s22s22p63s23p4
23. The order of first ionization enthalpies of the elements Li, (a) A < C < B < D (b) D < A < C < B
Be, B, Na is (c) A < B < C < D (d) A < B < D < C
(a) Li > Be > B > Na (b) Be > B > Li > Na 33. Which of the following elements has/have electron affinity
(c) Na > Li > B > Be (d) Be > Li > B > Na greater than S?
24. Which represents alkali metals (i.e. 1st group metals) based (a) O (b) Se
on IE1 and IE2 values (in kJ/mol)? (c) Te (d) None of these
IE1 IE2 34. Which of the following process is endothermic?
(a) X 500 1000 (a) Cl → Cl– (b) O → O–
(b) Y 600 2000 (c) N → N– (d) C → C–
(c) Z 550 7500
35. Which of the following configuration will have least electron
(d) M 700 1400
affinity?
25. First, second and third IP values are 100eV, 150eV and
(a) ns2np5 (b) ns2np2
1500eV. Element can be -
(c) ns2np3 (d) ns2np4
(a) Be (b) B (c) F (d) Na
26. The correct values of ionization enthalpies (in kJ mol–1) of 36. Second electron affinity of an element is
Si, P, Cl and S respectively are - (a) Always exothermic
(a) 786, 1012, 999, 1256 (b) Endothermic for few elements
(b) 1012, 786, 999, 1256 (c) Exothermic for few elements
(c) 786, 1012, 1256, 999 (d) Always endothermic
(d) 786, 999, 1012, 1256 37. Which of the following element is expected to have highest
27. Consider the following changes - electron affinity?
A → A+ + e– : E1 and A+ → A2+ + e– : E2 (a) 1s22s22p63s23p5
The energy required to pull out the two electrons are E1 (b) 1s22s22p3
and E2 respectively. The correct relationship between two (c) 1s22s22p4
energies would be (d) 1s22s22p5
(a) E1 < E2 (b) E1 = E2
(c) E1 > E2 (d) E1 ≥ E2 Electronegativity and its Application
Electron Affinity (Electron gain Enthalpy) 38. Electronegativity of the following elements increases in the
order -
28. Which of the following conversion is exothermic?
– (a) O < N < S < P
(a) Na → Na+ (b) Li → Li
– (b) P < S < N < O
(c) N → N (d) O → O2–
(c) P < N < S < O
(d) S < P < N < O
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MANTHAN
Chemistry Periodic Classification
Exercise-1 8. The ionic radii of N3–, O2– and F– are respectively given by -
(a) 1.36, 1.40, 1.71 (b) 1.36, 1.71, 1.40
PERIODIC TABLE (c) 1.71, 1.40, 1.36 (d) 1.71, 1.36, 1.40
1. Three element X, Y, Z are following Doberiner’s Triad rule. 9. Arrange the following element in increasing order of atomic
If the atomic weight of X and Y are 10 and 26 respectively, radii:
then atomic weight of Z will be (a) Na < K < Mg < Rb (b) K < Na < Mg < Rb
(a) 34 (b) 40 (c) 42 (d) 18 (c) Mg < Na < K < Rb (d) Rb < K < Mg < Na
2. If Aufbau rule is not followed, K (Z = 19) will be placed in 10. Which of following is arranged in decreasing order of size?
________ block. (a) Mg2+ > Al3+ > O2– (b) O2– > Mg2+ > Al3+
(a) s (b) p (c) d (d) f 3+ 2+
(c) Al > Mg > O 2– (d) Al3+ > O2– > Mg2+
3. In the general electronic configuration - (n – 2)f 1–14 11. In which of the following compounds, manganese show
(n – 1)d0–1 ns2, if value of n = 7 the configuration belongs to maximum radius?
(a) Lanthanoides (b) Actinoides (a) MnO2 (b) KMnO4
(c) Transition elements (d) None of these (c) MnO (d) K3[Mn(CN)6]
4. Given atomic number 15, 33, 51 represents the following 12. The correct order of atomic size would be
family - (a) Ni < Pd Pt (b) Pd < Pt < Ni
(a) Carbon family (b) Nitrogen family (c) Pt > Ni > Pd (d) Pd > Pt > Ni
(c) Oxygen family (d) None of these 13. Choose incorrect option regarding atomic size.
Atomic Size, Zeff (a) Zr Hf (b) Fe Co Ni
(c) Y La (d) All of the above
5. Correct order of radius of iso-electronic species is: –
(a) Cl– < S2– < K+ < Ca2+ 14. If the ionic radii of K+ and F are nearly the same (i.e., 1.34 Å),
then the atomic radii of K and F respectively are:
(b) S2– < Cl– < K+ < Ca2+
(a) 1.34 Å, 1.34 Å (b) 0.72 Å, 1.96 Å
(c) Ca2+ < K+ < Cl– < S2–
(c) 1.96 Å, 0.72 Å (d) 1.96 Å, 1.34 Å
(d) K+ < Ca2+ < Cl– < S2–
15. In which of the following pairs, atomic size of second atom
6. Which of the following is generally true regarding effective
is larger than the first one?
nuclear charge (Zeff)?
(a) Br, Cl (b) Na, Mg
(a) It increases on moving from left to right in a period.
(c) Sr, Ca (d) N, P
(b) It remains almost constant on moving top to bottom in
a group. 16. Which of the following configuration of atom has largest
radius?
(c) For isoelectronic species, as Z increases, Zeff decreases.
(a) 1s22s22p63s2 (b) 1s22s22p63s23p1
(d) Both (a) and (b)
(c) 1s22s22p63s23p3 (d) 1s22s22p63s23p5
7. From the given set of species, point out the species from
17. The maximum tendency to form unipositive ion is for the
each set having highest Zeff.
–
element with the electronic configuration-
(I) O2–, F , Na+ (a) 1s22s22p63s2 (b) 1s22s22p63s23p1
(II) Li, Be, Na (c) 1s22s22p63s23p2 (d) 1s22s22p63s23p3
–
(III) He, Li+, H
18. If internuclear distance between Cl atoms in Cl 2 is
I II III 10 Å & between H atoms in H2 is 2 Å, then calculate
(a) Na + Be Li+ internuclear distance between H & Cl (Electronegativity of
–
(b) O2– Li H H = 2.1 & Cl = 3.0).
–
(c) F Na He (a) 5.919 Å (b) 6.9 Å
(d) Na+ Be He (c) 7.919 Å (d) 4.91 Å
1
, 19. Which of the following is increasing order of paramagnetism? 29. Correct order of electron affinity is:
(a) Al < Mg < O < N (b) Mg < Al < N < O (a) S > P (b) S < P
(c) Mg < Al < O < N (d) N < O < Al < Mg (c) N > P (d) O > S
Ionisation Energy (Ionisation Enthalpy) 30. Among O, O+, O2+ and O2–, the species having most positive
20. Which of the following element has highest ionisation and most negative value of ΔHeg are, respectively
energy? (a) O+ and O (b) O2+ and O2–
(a) Oxygen (b) Nitrogen (c) O and O2– (d) O2– and O2+
(c) Fluorine (d) Helium 31. Of the following elements, which possess the highest electron
21. The correct order of stability of Al+, Al2+, Al3+ is- affinity?
(a) Al3+ > Al2+ > Al+ (b) Al2+ > Al3+ > Al+ (a) As (b) O
(c) Al2+ < Al+ > Al3+ (d) Al3+ > Al+ > Al2+ (c) S (d) Se
22. IP1 and IP2 of Mg are 178 and 348 Kcal mol–1. The enthalpy 32. Increasing order of electron affinity for the following
required for the reaction, Mg → Mg2+ + 2e– is configuration.
(a) + 170 Kcal (b) + 526 Kcal A. 1s22s22p3 B. 1s22s22p4
(c) – 170 Kcal (d) – 526 Kcal C. 1s22s22p63s23p3 D. 1s22s22p63s23p4
23. The order of first ionization enthalpies of the elements Li, (a) A < C < B < D (b) D < A < C < B
Be, B, Na is (c) A < B < C < D (d) A < B < D < C
(a) Li > Be > B > Na (b) Be > B > Li > Na 33. Which of the following elements has/have electron affinity
(c) Na > Li > B > Be (d) Be > Li > B > Na greater than S?
24. Which represents alkali metals (i.e. 1st group metals) based (a) O (b) Se
on IE1 and IE2 values (in kJ/mol)? (c) Te (d) None of these
IE1 IE2 34. Which of the following process is endothermic?
(a) X 500 1000 (a) Cl → Cl– (b) O → O–
(b) Y 600 2000 (c) N → N– (d) C → C–
(c) Z 550 7500
35. Which of the following configuration will have least electron
(d) M 700 1400
affinity?
25. First, second and third IP values are 100eV, 150eV and
(a) ns2np5 (b) ns2np2
1500eV. Element can be -
(c) ns2np3 (d) ns2np4
(a) Be (b) B (c) F (d) Na
26. The correct values of ionization enthalpies (in kJ mol–1) of 36. Second electron affinity of an element is
Si, P, Cl and S respectively are - (a) Always exothermic
(a) 786, 1012, 999, 1256 (b) Endothermic for few elements
(b) 1012, 786, 999, 1256 (c) Exothermic for few elements
(c) 786, 1012, 1256, 999 (d) Always endothermic
(d) 786, 999, 1012, 1256 37. Which of the following element is expected to have highest
27. Consider the following changes - electron affinity?
A → A+ + e– : E1 and A+ → A2+ + e– : E2 (a) 1s22s22p63s23p5
The energy required to pull out the two electrons are E1 (b) 1s22s22p3
and E2 respectively. The correct relationship between two (c) 1s22s22p4
energies would be (d) 1s22s22p5
(a) E1 < E2 (b) E1 = E2
(c) E1 > E2 (d) E1 ≥ E2 Electronegativity and its Application
Electron Affinity (Electron gain Enthalpy) 38. Electronegativity of the following elements increases in the
order -
28. Which of the following conversion is exothermic?
– (a) O < N < S < P
(a) Na → Na+ (b) Li → Li
– (b) P < S < N < O
(c) N → N (d) O → O2–
(c) P < N < S < O
(d) S < P < N < O
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