Practice Exercise

L-1 Coaching

Chemistry

LEVEL-1 Single Correct Answer Type 1. 2.

The element having electronic configuration 4f 14 5d0 6s 2 belongs to (a) d – block, 12th group (b) f-block, III B group (c) f-block, 14th group (d) s-block, 2nd group Element with the electronic configuration given below, belong to which group in the periodic table

1s 2 ,2s 2 2p6 ,3s 2 3p6 3d10 ,4s 2 4p6 4d10 ,5s 2 5p3 3.

4.

5.

6.

7. 8.

9.

10.

11.

(a) 3rd (b) 5th (c) 15th (d) 17th The places that were left empty by Mendeleef were, for(a) Aluminium & Silicon (b) Gallium and germanium (c) Arsenic and antimony (d) Molybdenum and tungsten Mendeleef period table is based on(a) atomic number (b) increasing number of protons (c) electronic configuration (d) None of the above Which are correct match(i) Eka silicon-Be (ii) Eka aluminium-Ga (iii) Eka manganese-Tc (iv) Eka scandium –B (a) ii, iii (b) i, ii, iv (c) i, iv (d) all Atomic no. is the base of(i) Lother meyer curve (ii) Newland octave rule (iii) Modern periodic table (iv) Deberiener traid rule (v) Long from of periodic table (a) i, ii, iv (b) iii, v (c) i, iv (d) i, iii, v Which of the following elements belongs to same period(a) Zn, Cd, Hg (b) Fr, Ra, U (c) K, Ca, Ag (d) None The atom having the valence shell electronic configuration 4s  4p 2 would be in(a) group II A and period 3 (b) group II B and period 4 (c) group IV A and period 4 (d) group IV A and period 3 Elements with similar chemical properties(a) occur only within the same period (b) have identical atomic mass (weight) (c) have identical number of neutrons (d) have the same number of electrons in the outer shell Z eff (I) ……… along the period and (II) ……… along the group (a) (I) Increases, (II) Increases (b) (I) decreases, (II) Increases (c) (I) decreases (II) decreases (d) (I) Increases, (II) decreases Ionic radii are: (a) inversely proportional to effective nuclear charge (b) inversely proportional to square of effective nuclear charge. (c) directly proportional to effective nuclear charge. (d) directly proportional to square of effective nuclear charge. 1

L-1 Coaching

Chemistry

12.

Which of the following order of radii is correct(b) H  Li  H

(a) Li < Be < Mg 13. 14. 15.

Which of the following is not different for an atom and its corresponding ion(a) number of electrons (b) nuclear charge (c) properties (d) size Atomic radii of fluorine and neon in Angstrom units are given by(a) 0.72, 1.60 (b) 1.60, 1.60 (c) 0.72, 0.72 (d) None of these Which of the following has largest radius(a) 1s2 ,2s2 ,2p6 ,3s2

16. 17.

18.

19.

(b) 1s2 ,2s2 ,2p6 ,3s2 ,3p1 (c) 1s2 ,2s2 ,2p6 ,3s2 ,3p3 (d) 1s2 ,2s2 ,2p6 ,3s2 ,3p5

In the isoelectronic species the ionic radii (A) of N 3  , O 2  and F  are respectively given by(a) 1.36, 140, 1.71 (b) 1.36, 1.71, 1.40 (c) 1.71, 1.40, 1.36 (d) 1.71, 1.36, 1.40 The covalent radius of potassium atom is 0.203 nm. The radius of the potassium ion in nanometer will be(a) 0.133 (b) 0.231 (c) 0.234 (d) 0.251 In an anion(a) Number of proton decreases (b) protons are more than electrons (c) effective nuclear charge is more (d) radius is larger than neutral atom If the ionic radii of K  and F  are about 1.34 A 0 each, then the expected values of atomic radii of K and F should be respectively. 0

20.

21.

22. 23.

24. 25.

(d) Na   F  O2

(c) O < F < Ne

0

0

0

(a) 1.34 and 1.34 A (b) 2.31 and 0.64 A (c) 0.64 and 2.31 A (d) 2.31 and 1.34 A The ionization potential of isotopes of an element will be(a) same (b) different (c) depends on atomic masses (d) depends on number of neutrons Compared to the first ionization potential, the value of second ionization potential of an element is(a) Negligible (b) smaller (c) greater (d) double Ionisation energy increases in the order(a) Be, B, C, N (b) B, Be, C, N (c) C, N, Be, B (d) N, C, Be, B Highest ionization potential in a period is shown by(a) alkali metals (b) noble gases (c) halogens (d) representative elements With reference to ionization potential which one of the following sets is correct(a) Li > K > B (b) B > Li > K (c) Cs > Li > K (d) Cs < Li < K Which has the lowest IE(a) 3d 2

(b) 4s 1

(c) 3p 3

(d) 2p6

26.

In which case the energy released is minimum-

27.

(a) Cl  Cl  (b) P  P  (c) N  N  (d) C  C  In the formation of a chloride ion, from an isolated gaseous chlorine atom, 3.8 eV energy is released, which would be equal to(a) electron affinity of Cl 

28. 29.

(b) ionization potential of Cl

(c) electronegativity of Cl (d) ionization potential of Cl  Which of the following configuration will have least electron affinity (a) ns 2 np 5 (b) ns 2 np 2 (c) ns 2 np 3 (d) ns 2 np 4 Which of the following element will form most sable bivalent anion(a) fluorine (b) oxygen (c) chlorine (d) nitrogen 2

L-1 Coaching

Chemistry

30.

Outermost electronic configuration of the most electronegative element is(a) ns 2 np 3

31.

32.

36.

(b) Be(OH) 2 , Mg(OH) 2

(c) B(OH) 3 , Be(OH) 2 (d) Be(OH) 2 , Zn(OH) 2

(b) BeCl 2

(c) BCl 3

(d) CCl 4

(b) MgO

(c) Na 2 O

(d) CaO

Strongest acid is (a) Al2 O 3

35.

(d) ns 2 np 5

Which has highest melting point (a) LiCl

34.

(c) ns 2

Electronegativity values for elements are useful in predicting(a) Bond energy of a molecule (b) polarity of a molecule (c) nature of an oxide (d) all The pair of amphoteric hydroxides is (a) Al(OH) 3 , LiOH

33.

(b) ns 2 np 6

In which block 106th element belongs (a) s-block (b) p-block (c) d-block (d) f-block Which of the following property displays progressive increase down a group in the Bohr's periodic table (a) Electronegativity (b) Electron affinity (c) Ionization potential (d)Size of the atom

LEVEL-2 Single Correct Answer Type 1. In the periodic table, the metallic character of elements(a) decrease from left to right across a period and on descending a group (b) decreases from left to right across a period and increases on descending a group (c) increases from left to right across a period and on descending a group (d) increases from left to right across a period and decreases on descending a group 2. Which of the following is/are Doeberiners triad(i) P, As, Sb (ii) Cu, Ag, Au (iii) Fe, Co, Ni (iv) S, Se, Te Correct answer is(a) i and ii (b) ii and iii (c) i and iv (d) all 3. Which of the following sets of elements follows Newland’s octave rule(a) Be, Mg, Ca (b) Na, K, Rb (c) F, Cl, Br (d) B, Al, Ga 4. In a period the elements are arranged in(a) decreasing order of nuclear charge (b) decreasing order of No. of electrons (c) increasing order of nuclear charge (d) in order of same nuclear charge 5. Justification of putting H in VII A group is(a) H is gas (b) H is non metal (c) it form NaH like salt (d) It has ortho and para allotropes 6. Which of the following element was absent in the Mendeleeve’s periodic table(a) Tc (b) Si (c) B (d) F 7. Atomic number of Ag is 47. In the same group the atomic number of elements placed above and below Ag will be(a) 37, 67 (b) 29, 79 (c) 39, 69 (d) 18, 28 8. An example of metalloid is(a) 12 Mg (b) 16 S (c) 14 Si (d) 18 Ar 9. Which statements is false(a) screening effect increasing down the group (b) Zeff increases down the group (c) Zeff, increases in a period (d) all 3

L-1 Coaching

Chemistry

10.

11.

12. 13.

14. 15.

16.

17.

18.

19.

Effective nuclear charge in group generally(a) increases down the group (b) decrease down the group (c) remains constant (d) first increases than decreases The screening effect of d-electrons is(a) equal to the p-electrons (b) much more than p –electron (c) same as f-electrons (d) less than p-electrons In which of the following compounds Mn shows maximum radius(a) MnO 2 (b) KMnO 4 (c) MnO (d) K 3[Mn(CN)6 ]

K  , Ar, Ca2  and S 2  contains(a) same electronic configuration and atomic volume (b) different electronic configuration but same IP (c) same electric configuration but different atomic volume (d) none Which has the lowest anion to cation size atom(a) LiF (b) NaF (c) CsI (d) CsF The crystal of which of the following ionic compounds would you expect the minimum distance between centres of cations and anions(a) CsF (b) CsI (c) LiI (d) LiF The best reason to account for the general tendency of atomic diameters to decrease as the atomic number increase within a period of the periodic table is the fact that(a) outer electrons repel inner electrons (b) closer packing among the nuclear particles is achieved (c) the number of neutrons increases (d) the increasing nuclear charge exerts a greater attractive force on the electrons Correct orders of I st I.P. are(i) Li < B < Be < C (ii) O < N < F (iii) Be < N < Ne (a) i, ii (b) ii, iii (c) i, iii (d) i, ii, iii The second ionization potentials in electron volts of oxygen and fluorine atoms are respectively given by(a) 35.1, 38.3 (b) 38.3, 38.3 (c) 38.3, 35.1 (d) 35.1, 35.1 nd rd A sudden large jump between the values of 2 and 3 IPs of an element would be associated with the electrons configuration(a) 1s2 ,2s2 ,2p6 ,3s1

20.

21.

(b) 1s2 ,2s2 ,2p6 ,3s2 ,3p5 (c) 1s2 ,2s2 ,2p6 ,3s2 ,3p2

(d) 1s2 ,2s2 ,2p6 ,3s2

In which of the following pairs, the ionization energy of the first species is less than that of the second(a) O , O 2  (b) S, P (c) N, P (d) Be , Be The value of IP1 , IP2 , IP3 and IP4 of an atom are respectively 10.5 eV, 21eV, 38eV and 170.6 eV. The electronic configuration of the atom will be(a) 1s2 ,2s2 ,2p6 ,3s1

22. 23.

(b) 1s2 ,2s2 ,2p6 ,3s2 ,3p1 (c) 1s2 ,2s2 ,2p6 ,3s2 ,3p3

The correct order of electron affinity is(a) Be < B < C < N (b) Be < N < B < C Second electron affinity of an element is(a) always exothermic (c) Exothermic for few elements

(c) N < Be < C < B

(d) 1s2 ,2s2 ,2p6 ,3s2 (d) N < C < B < Be

(b) endothermic for few elements (d) always endothermic 4

L-1 Coaching

Chemistry

24.

25. 26. 27.

28.

Fluorine has the highest electronegativity among the ns 2 np 5 group on the Pauling scale, but the electron affinity of fluorine is the less than chlorine because: (a) The atomic number of fluorine is less than that of chlorine (b) Fluorine being the first member of the family behaves in an unusual manner. (c) Chlorine can accommodate an electron better than fluorine by utilizing its vacant 3d-orbital (d) Small size, high electron density and increase in electron repulsion makes addition of an electron to fluorine less favourable than that in the case of chlorine Electronegativity scale of pauling is based upon(a) bond length (b) bond energy (c) atomic radius (d) covalent radius Correct order of electronegativity of N, P, C and Si is(a) N < P < C < Si (b) N > C > Si > P (c) N = P > C = Si (d) N > C > P > Si Mulliken scale of electrnegativity uses the concept of(a) E.A. and EN (b) E.A. and atomic size (c) E.A. and I.P. (d) E.A. and bond energy Correct order of electronegative difference between bonded atom is: (a) AlCl3  MgCl 2  NaCl (b) NaCl  AlCl3  MgCl 2 (c) NaCl  MgCl 2  AlCl3

29.

30.

(d) MgCl 2  NaCl  AlCl3

A section of periodic table is given below with element A, B and X, Y in the groups. Which of the bonds is least polar? Metal Non-Metal A X B Y (a) AX (b) AY (c) BX (d) BY Cs

Lowest I.P.

He

Highest I.P.

What prediction can be made regarding bond formation between Cs and He: (a) Ionic 31.

(b) Covalent

(c) Metallic

(d) No bond at all

In which of the following arrangements the order is NOT according to the property indicated against it (a) Al3  Mg2  Na   F  : Increasing ionic size

32.

(b) B  C  N  O : Increasing first ionization enthalpy (c) I  Br  F  Cl : Increasing electron gain enthalpy (with negative sign) (d) Li  Na  K  Rb : Increasing metallic radius The incorrect statement among the following is (a) The first ionisation potential of Al is less than the first ionisation potential of Mg (b) The second ionisation potential of Mg is greater than the second ionisation potential of Na (c) The first ionisation potential of Na is less than the first ionisation potential of Mg (d) The third ionisation potential of Mg is greater than the third ionisation potential of Al

33.

The second ionisation potential of an element M is the energy required to (a) Remove one mole of electron from one mole of gaseous anion (b) Remove one mole of electron from one mole of gaseous cation of the element (c) Remove one mole of electron from one mole of monovalent gaseous cation of the element (d) Remove 2 moles of electrons from one mole of gaseous atoms 5

L-1 Coaching

Chemistry

34.

35.

The first ionisation energies of alkaline earth metals are higher than those of the alkali metals. This is because (a) There is increase in the nuclear charge of the alkaline earth metals (b) There is a decrease in the nuclear charge of the alkaline earth metals (c) There is no change in the nuclear charge (d) None of the above The ionization energy of nitrogen is more than that of oxygen because (a) Nitrogen has half filled p-orbitals (b) Nitrogen is left to the oxygen in the same period of the periodic table (c) Nitrogen contains less number of electrons (d) Nitrogen is less electronegative

LEVEL-3 Single Correct Answer Type 1. Which is not anomalous pair of element in the Medeleeves periodic table(a) Ar and K (b) Co and Ni (c) Te and I (d) Al and Si 2. Elements which occupied position in the lother meyer curve, on the peaks, were(a) alkali metals (b) Highly electro positive elements (c) elements having large atomic volume (d) all 3. The formula for effective nuclear charge is (If  is screening constant)4. 5.

6.

7. 8.

(a) Z   (b) Z   In sodium atom the screening is due to-

(c) Z 1

(d) Z

(a) 3s 2 ,3p6

(c) 1s 2 ,2s 2 ,2p6

(d) 1s 2 ,2s 2

(b) 2s 1

In the lithium atom screening effect of valence shell electrons is caused by(a) electrons of K and L shell (b) electrons of K shell st nd (c) two electrons of 1 and one of 2 shell (d) none Which of the following option is correct? (i) On moving from left to right in a period screening constant value increases (ii) In a, s, p, d, f-orbitals the order of screening effect is s > p > d > f in a given shell (iii) In any period from left to right effective nuclear charge increases so electronegativity is also increases (iv) when  increases, Z eff also increase (a) TTTF (b) FFFT (c) FFTT (d) TTFF The increasing order of effective nuclear charge in Na, Al, Mg and Si atoms (a) Na < Mg < Si < Al (b) Na < Mg < Al < Si (c) Mg < Na < Al < Si (d) Na = Mg = Al = Si An increase in both atomic and ionic radii with atomic number occurs in any group of the periodic 0

0

table and in accordance with this the ionic radii of Ti (IV) and Zr (IV) ions are 0.68 A and 0.74 A 0

respectively, but for Hf (IV) ion, the ionic radius is 0.75 A , which is almost the same as that for Zr (IV) ion. this is due to: (a) greater degree of covalency in compounds of Hf 4  (b) lanthanide contraction (c) actinide contraction (d) difference in co-ordination number of Zn 4  and Hf 4  in their compounds

6

L-1 Coaching

Chemistry

9.

In general, the configuration of lanthanides is ( n  2 ) f 1 14 ( n  1)s2 p6d0  1n s2 . It has been observed that, with increase in atomic number of lanthanides, there is a decrease in ionic radii from La (1.22 0

10.

0

A ) to Lu (0.99 A ). The reason for decrease in ionic radii is an increase in: (a) electronegative character (b) valency electrons and number of shells (c) atomic and ionic volumes (d) nuclear attraction for valence electrons leading to inward shrinking of shell Which of the following transitions involves maximum amount of energy –

(a) M ( g )  M(g )

(b) M(g )  M ( g )

(c) M ( g )  M 2 (g )

(d) M 2 (g )  M 3 (g )

11.

Which of the following statements is wrong for fluorine(a) it’s standard reduction potential is highest (b) it is most electronegative element (c) bond energy of F2  Cl 2 (d) Fluorine has highest electron affinity

12.

O(g )  2e   O2 (g )E = 744.7 KJ/mole. The positive value of E is due to-

(a) O  O 2

(b) Mg   Mg 2

(c) Cl  Cl 

(d) F  F 

13.

In which of the following process energy is liberated –

14.

(a) Cl  Cl  +e (b) HCl  H  Cl  (c) Cl  e  Cl  Be and Mg have zero value of electron affinities, because-

(d) O  e  O2

(a) Be and Mg have (He) 2s 2 and (Ne) 3s 2 configuration respectively (b) 2s and 3s orbitals are filled to their capacity (c) Be and Mg are unable to accept electron (d) all the above are correct 15.

0

0

16.

17. 18. 19.

20.

0

The X – X bond length is 1.00 A and C – C bond length is 1.54 A . If electronegativities of ‘X’ and ‘C’ are 3.0 and 2.0 respectively, the C – X bond length is likely to be0

0

0

(a) 1.27 A (b) 1.18 A (c) 1.08 A (d) 1.28 A The percent ionic character in the molecules A-B is calculated by the formula 100  [0.16(XA XB )  0.035( XA  XB )2 ] where XA & X B are the electronegativities of A & B respectively. Thus, the maximum ionic character is associated with(a) H – F (b) H – Cl (c) H – Br (d) H – I The elements which occupy the peaks of ionisation energy curve, are (a) Na, K, Rb, Cs (b) Na, Mg, Cl, I (c) Cl, Br, I, F (d) He, Ne, Ar, Kr Ionic radii of (a) Ti4  Mn7 (b) 35 Cl  37 Cl  (c) K   Cl  (d) P3  P 5 The ionization energy of an element is (a) The same as the electron affinity of the element (b) Equal in magnitude but of opposite sign to the electron affinity of the element (c) The energy released when an electron is added to an atom of the element (d) The energy required to remove the outermost electron of an atom of the element The statement that is not correct for the periodic classification of elements is (a) The properties of elements are the periodic functions of their atomic numbers (b) Non-metallic elements are lesser in number than metallic elements (c) The first ionisation energies along a period do not vary in a regular manner with increase in atomic number (d) For transition elements the d -sub-shells are filled with electrons monotonically with increase in atomic number 7

L-1 Coaching

Chemistry

21.

Which of the following explanation is best for not placing hydrogen in either the group of alkali metals or halogens (a) The ionization energy of hydrogen is two high for group of alkali metals, but too low of halogen group (b) Hydrogen can form compounds with all other elements (c) Hydrogen is much lighter element than the alkali metals or the halogens (d) None of the above 

1. 2. 3. 4. 5. 6.

b c b d a b

7. 8. 9. 10. 11. 12.

a c d d a b

13. 14. 15. 16. 17. 18.

1. 2. 3. 4. 5.

b c a c c

6. 7. 8. 9. 10.

a b c b c

11. 12. 13. 14. 15.

d c c d d

1. 2. 3.

d a a

4. 5. 6.

c b a

7. 8. 9.

b b d

Answer – key LEVEL-1 b 19. a 20. a 21. c 22. a 23. d 24. LEVEL-2 16. d 17. d 18. c 19. d 20. b LEVEL-3 10. d 11. d 12. c

b a c b b b

25. 26. 27. 28. 29. 30.

21. 22. 23. 24. 25.

b b d d b

13. 14. 15.

c d d

b c d c b d 26. 27. 28. 29. 30. 16. 17. 18.

31. 32. 33. 34. 35. 36. d c a b d a d d

31. 32. 33. 34. 35. 19. 20. 21.

d d b a c d b b c a a d c a

8