Solved MCQs Periodic Classification
Solved MCQs Periodic Classification:
Q1. Which of the following processes involves the absorption of energy?
a) Cl + e– → Cl–
b) O– + e‑ → O2-
c) O + e– → O–
d) S + e– → S–
Ans 1. b) O– + e‑ → O2- As the electron is being added to the anion, whereas in all rest of three, the electron is being added to a –neutral atom which will not have as much repulsion as in the case of O–.
Q2. Electronic Configuration of most electro negative element is
a) 1s2 2s2 2p6 3s1
b) 1s2 2s2 2p6 3s2 3p5
c) 1s2 2s2 2p5
d) 1s2 2s2 2p6 3s2 3p6
Ans 2. c) 1s2 2s2 2p5
1s2 2s2 2p6 3s2 3p6 has completely filled subshell so will not attract e–
Q3. The correct order of electron gain enthalpy with the negative sign of F, Cl, Br, and I, having atomic number 9, 17, 35, and 53 respectively are
(a) I > Br > Cl > F
(b) F > Cl > Br > I
(c) CI > F > Br > I
(d) Br > CI > I > F
Ans 3. (c) CI > F > Br > I
Q4. The element with positive electron gain enthalpy is
(a) hydrogen
(b) sodium
(c) oxygen
(d) none
Ans 4. (d) none
Q5. Which of the following species has the highest electron affinity?
(a) F – (b) O (c) O– (d) Na+
Ans5. (b) O
Q6. Elements of which of the following groups will form anions most readily?
(a) Oxygen family (b) Nitrogen family
(c) Halogens (d) Alkali metals
Ans 6. (c) Halogens
Q7. The correct order of electronegativities of N, O, F and P is
(a) F > N > P > O
(b) F > O > P > N
(c) F > O > N > P
(d) N > O > F > P
Ans 7. (c) F > O > N > P
Q8. Among the elements B, Mg, Al and K, the correct order of increasing metallic character is
(a) B < Al < Mg < K
(b) B < Mg < Al < K
(c) Mg < B < Al < K
(d) Mg < Al < B < K
Ans 8. (a) B < Al < Mg < K
Q9. In which of the following options order of arrangement does not agree with the variation of the property indicated against it?
(a) Al3+ < Mg2+ < Na+ < F– (increasing ionic size)
(b) B < C < N < O (increasing first ionization enthalpy)
(c) I < Br < F < Cl (increasing electron gain enthalpy)
(d) Li < Na < K < Rb (increasing metallic radius)
Ans 9. (b) B < C < N < O (increasing first ionization enthalpy)
Q10. Which one of the following orders presents the correct sequence of the increasing basic nature of the given oxides?
(a) Al2O3 < MgO < Na2O < K2O
(b) MgO < K2O < Al2O3 < Na2O
(c) Na2O < K2O < MgO < Al2O3
(d) K2O < Na2O < Al2O3 < MgO
Ans 10. (a) Al2O3 < MgO < Na2O < K2O
Q11. Which of the following sets has strongest tendency to forms anions?
(a) Ga, In, TI (b) Na, Mg, Al
(c) N, O, F (d) V, Cr, Mn
Ans 11. (c) N, O, F
Q12. To which block of the periodic table does the element with atomic number 56 belong?
(a) s block (b) p block
(c) d block (d) f block
Ans 12. (a) s block
Q13. The electronic configurations of four elements are given below. Which elements do not belong to the same family as others?
(a) [Xe] 4f14 5d10 6s2 (b) [Kr] 4d10 5s2
(c) [Ne] 3s2 3p5 (d) [Ar] 3d10 4s2
Ans 13. (c) [Ne] 3s2 3p5
Q14. The similarity between Li and Mg is due to
(a) similar electronic configuration (b) same charge
(c) same principal quantum number (d) similar electronegativity
Ans 14. (d) similar electronegativity
Solved MCQs Periodic Classification
Q15. The correct order of second ionization potential of carbon, nitrogen, oxygen, and fluorine is
a) C > N > O > F
b) O > N > F > C
c) O > F > N > C
d) F > O > N > C
Ans 15. (c) O > F > N > C. After removal of first electron the configuration of these elements is
C+ 1s2 2s2 2p1 O+ 1s2 2s2 2p3 N+ 1s2 2s2 2p2 F+ 1s2 2s2 2p4
Out of these, O has a half-filled p subshell so to remove e will be most difficult. O will have maximum ionization potential then C will leave their readily so as to have empty p subshell thus the potential will be least. Out of N and F, F is more electronegative than N and N is more electronegative than C thus their ionization potential will be in the same order. Thus the order will be C) O > F > N > C
Q16. The first ionization potential of Na, Mg, Al, and Si are in the order
a) Na < Mg > Al < Si
b) Na > Mg > Al > Si
c) Na < Mg > Al < Si
d) Na > Mg > Al > Si
Ans 16. c) Na < Mg > Al < Si. Across the period the ionization potential increases as the electron enter the same shell so the effective nuclear charge increases thus the order for Na, Al, Si is Na < Al < Si but Mg has the maximum ionization potential because its configuration is 1s2 2s2 2p6 3s2 i.e. completely filled 3s subshell thus more stable have the order is Na < Mg > Al > Si
Q17. Which electronic configuration of an element has an abnormally high difference between second and third ionization energy.
a) 1s2 2s2 2p6 3s1
b) 1s2 2s2 2p6 3s2 3p1
c) 1s2 2s2 2p6
d) 1s2 2s2 2p6 3s2
Ans 17. (c)1s2 2s2 2p6
Q18. The set representing the correct order of ionic radius is
(a) Li+2 > Be+2 > Na+2 > Mg+2
(b) Na+2 > Li+2 > Mg+2 > Be+2
(c) Li+2 > Na+2 > Mg+2 > Be+2
(d) Mg+2 > Be+2 > Li+2 > Na+2
Ans 18. (b) Na+2 > Li+2 > Mg+2 > Be+2
Que 19. Atomic radii of fluorine and neon in Angstrom units are respectively given by
(a) 0.72, 1.60 (b) 1.60, 1.60
(c) 0.72, 0.72 (d) None of these
Ans 19. (a) 0.72, 1.60
Que 20. Which one of the following is the smallest in size?
(a) N3- (b) O2- (c) F– (d) Na+
Ans 20. (d) Na+
Que 21. The correct order of atomic radii is
(a) N < Be < B (b) F– < O2- < N3-
(c) Na < Li < K (d) Fe3+ < Fe2+ < Fe4+
Ans 21. (b) F– < O2- < N3-
Que 22. The correct sequence which shows decreasing order of the ionic radii of the elements is:
(a) Na+ > F– > Mg2+ > O2- > Al3+
(b) O2- > F– > Na+ > Mg2+ > Al3+
(c) Al3+ > Mg2+ > Na+ > F– > O2-
(d) Na+ > Mg2+ > Al3+ > O2- > F–
Ans 22. (b) O2- > F– > Na+ > Mg2+ > Al3+
Que 23. Among the elements Ca, Mg, P and Cl, the order of increasing atomic radii is:
(a) Ca < Mg < P < Cl
(b) Mg < Ca < Cl < P
(c) Cl < P < Mg < Ca
(d) P < Cl < Ca < Mg
Ans 23. (c) Cl < P < Mg < Ca
Que 24. The element with the highest first ionization potential is
(a) Boron (b) Carbon
(c) Nitrogen (d) Oxygen
Ans 24. (c) Nitrogen
Que 25. Which of the following has the maximum number of unpaired electrons?
(a) Mg2+ (b) Ti3+
(c) V3+ (d) Fe2+
Ans 25. (d) Fe2+
Que 26. The incorrect statement among the following is
(a) The first ionization potential of Al is less than the first ionization potential of Mg
(b) The second ionization potential of Mg is greater than the second ionization potential of Na
(c) The first ionization potential of Na is less than the first ionization potential of Mg
(d) The third ionization potential of Mg is greater than the third ionization potential of Na
Ans 26. (b) The second ionization potential of Mg is greater than the second ionization potential of Na
Que 27. Ionization energies of the following elements increases in the order
(a) N < O < P < S (b) O < N < S < P
(c) P < S < N < O (d) S < P < O < N
Ans . (d) S < P < O < N
Solved MCQs Periodic Classification
