Bits
Multiple Choice Questions
1. Chemical bond formation between atoms in terms of valency electrons was explained by
A) Kossel and Lewis B) Slater C) London D) Heitler
2. The electrons present in the outermost orbit of an atom are called
A) Last electrons B) Outer electrons C) Bond electrons D) valency electrons
3. Number of valency electrons in Oxygen atom are
A) 5 B) 6 C) 7 D) 4
4. Valency of Oxygen atom is
A) 1 B) 2 C) 4 D) 5
5. Why atoms are combining
A) to get stability by gaining of eight electrons in the outermost orbit
B) to get stability by losing energy
C) to get stability by gaining of eight electrons in the outermost orbit, to get stability by losing energy
D) None of these
6. Inert gases do not enter into chemical reaction. It is due to
A) its stability
B) eight electrons present in the energy level.
C) do not react with other elements.
D) eight electrons present in outermost orbit.
7. The inert gas which do not having eight electrons in the outermost orbit is
A) Ne B) Ar C) Xe D) He
8. The correct Lewis dot structure of Krypton is
9. The bond formed by the transfer of electrons from outer orbit of one atom to outer orbit of another atom is called
A) Ionic bond B) Covalent bond C) Single bond D) Double bond
10. Which of the following is an ionic compound among them
A) H2O B) NH3 C) MgCl2 D) CH4
11. Which of the following is not an ionic compound among them.
A) NaCl B) Na2O C) AlCl3 D) BeCl2
12. The bond formed by sharing of electrons is called
A) Ionic Bond B) Co-ordinate bond C) Electrovalent bond D) Covalent bond
13. The molecule having covalent bond is
A) MgCl2 B) BeCl2 C) AlCl3 D) NaCl
14. The molecule do not having a covalent bond is
A) NH3 B) NaCl C) F2 D) O2
15. Both Ionic and Covalent bonds containing molecule is
A) H2O B) NH3 C) KCN D) KCl
16. Element X combine with Oxygen to form X2O compound. The number of electrons present in the outermost orbit of X atom are
A) 5 B) 2 C) 1 D) 3
17. Which of the following molecule contains a Triple Bond
A) O2 B) N2 C) Cl2 D) F2
18. Which one of the molecule is pyramidal
A) CH4 B) H2O C) NH3 D) HCl
19. Bond angle in water molecule
A) 90° B) 104° 31' C) 107° 8' D) 120°
20. H-N-H bond angle in Ammonia molecule is
A) 104° 31' B) 109° 28' C) 120° D) 107° 48'
21. The covalent bond depend upon
A) overlapping of orbitals B) energy of orbitals
C) shapes of orbitals D) size of the orbitals
22. Two elements X and Y have electronic configuration 1s2 2s2 2p6 3s1 and 1s2 2s2 2p6 3s2 3p5 respectively. If X and Y combine the type of bond formed is
A) Covalent B) Ionic C) Van der Wall bond D) None of these
23. The number of σ and π bonds present in N2 molecule are
A) 1 and 3 B) 1 and 2 C) 2 and 1 D) 2 and 2
24. Valency bond theory was proposed by
A) Linus Pauling B) Gillespic and Nyholm
C) Lewis and Kossel D) Slater
25. If the mass number is 12 and atomic number is 6 for the elements X, then the kind of bond present in XH4 are
A) Ionic bond B) Covalent bond C) Coordinate Covalent bond D) None of these
26. Match the following.
| 1) H2O Molecule | a) Planer triangular shape |
| 2) BeCl2 molecule | b) Pyramidal shape |
| 3) BF3 molecule | c) V - shape |
| 4) NH3 molecule | d) Linear |
A) 1-c, 2-d, 3-b, 4-a B) 1-d, 2-c, 3-b, 4-a C) 1-c, 2-d, 3-a, 4-b D) 1-c, 2-b, 3-d, 4-a
27. Match the following.
| 1) 104° 31' | a) NH3 |
| 2) 180° | b) BF3 |
| 3) 107° 48' | c) BeCl2 |
| 4) 120° | d) H2O |
A) 1-d, 2-c, 3-b, 4-a B) 1-d, 2-a, 3-c, 4-b C) 1-d, 2-c, 3-a, 4-b D) 1-a, 2-b, 3-c, 4-d
28. Match the following.
| 1) Covalent bond | a) Kosell |
| 2) VSEPRT Theory | b) Kossel and Lewis |
| 3) Ionic bond | c) G.N. Lewis |
| 4) Electron theory of valence | d) Sidgwick and Powell |
A) 1-c, 2-d, 3-a, 4-b B) 1-c, 2-d, 3-b, 4-a C) 1-c, 2-a, 3-b, 4-d D) 1-a, 2-b, 3-c, 4-d
29. Which of the following is incorrect?
A) Electron theory of valence - Kossel and Lewis
B) VSEPRT theory - Sidgwick and Powell
C) Valency bond theory - Linus Pauling
D) Octect theory - Dobereiner
30. X+2 electronic configuration is 1s2 2s2 2p6 but what is X here
A) Mg B) Mn C) Cl D) Cu
31. Which element represents 
A) Ne B) Ar C) Kr D) All the above
32. The bond angle of H2O molecule is
A) 104° 31' B) 107° 48' C) 109° 28' D) 120°
33. Which of the following not have sp3 hybridisation?
A) CH4 B) NH3 C) BF3 D) H2O
34. How many π bonds are present in CH4?
A) 0 B) 1 C) 2 D) 3
35. A covalent bond is formed by
A) Sharing of electrons
B) Repulsion of atoms between two atoms
C) Transfer of electrons
D) Sharing of electrons by only single atom
36. 2, 8, 1 and 2, 8, 7 are electronic configuration of A and B elements combine to form a molecule its formula is
A) AB B) AB2 C) AB3 D) A3B
37. Shape of H2O molecule is
A) Linear B) Pyramid C) Tetrahedral D) Angular
38. In NaCl crystal, how many Cl - ions are there around the Sodium ion
A) 5 B) 6 C) 7 D) 8
39. The total number of electrons that take part in forming bonds in O2 is
A) 2 B) 4 C) 6 D) 8
40. The most stable substance of the following is
A) N B) O C) Ne D) Mg
41. Which of the following shows ionic bonding?
A) CO2 B) O2 C) MgCl2 D) N2
42. The element X does not usually form compounds with atoms of other elements. Which one of the following could be the electronic configuration of X ?
A) 1s2 2s2 2p1 B) 1s2 2s2 2p4 C) 1s2 2s2 2p5 D) 1s2 2s2 2p6
43. The number of electrons provided by Chlorine for sharing in HCl bonding
A) 3 B) 7 C) 4 D) 1
44. Multiple covalent bonds exist in the molecule of
A) HCl B) H2 C) F2 D) N2
45. Which of the following has the highest bond angle?
A) BeCl2 B) CH4 C) H2O D) NH3
46. Lewis structure of Ammonia (NH3) is
52. Lewis structure of BeCl2 is
53. What is the bond length of H - F (Å) ?
A) 0.74 B) 1.44 C) 0.901 D) 0.918
54. What is the bond length of F - F (Å)
A) 0.74 B) 0.91 C) 1.27 D) 1.44
55. Bond energy of H - Cl
A) 410 kJ mol -1 B) 482 kJ mol -1 C) 432 kJ mol -1 D) 460 kJ mol -1
56. Bond energy of H - C (of CH4)
A) 0.96 kJ/ mol B) 1.01 kJ/ mol C) 1.10 kJ/ mol D) 1.27 kJ/ mol
57. Choose the correct form of the diagram representing H2 molecule
58. The molecule with two bond-pairs and two lone-pairs on the central atom
A) NH3 B) BF3 C) CH4 D) H2O
59. The maximum number of covalent bonds that can exist among a pair of atom is
A) 1 B) 2 C) 3 D) 4
60. The valence shell of the central atom of a molecule has four bond-pairs of electrons. Shape of the molecule is
A) Tetrahedral B) Linear C) Plane Triangular D) Square Planar
61. In a double bond, there are
A) two σbonds B) two π bonds C) one σ bond and one π bond D) None of these
62. Orbitals forming π bonds
A) s B) p C) s and p D) None of these
63. In the formation of BeCl2 molecule, the central atom undergoes the following type of hybridisation.
A) sp B) sp2 C) sp3 D) σ sp3 - s
64. In the formation of Ammonia molecule, the Nitrogen atom undergoes the following type of hybridisation.
A) sp B) sp2 C) sp3 D) σ sp3 - s
65. The number of π bonds present in N2 molecules
A) 0 B) 1 C) 2 D) 3
66. A triple bond is made up of
A) 3 σ bonds B) 3 π bonds C) 1σ and 2π bonds D) 1π and 2 σ bonds
67. Hydrogen atom gets stability by achieving the configuration of
A) He B) Li C) Be D) Ne
68. s - p overlap is present in
A) H2 B) O2 C) Cl2 D) HCl
69. Crystal Lattice of Sodium Chloride contains
A) Na+ and Cl - ions B) Na and Cl atoms C) NaCl molecules D) None of these
70. Except which of the following gas all other noble gases have octet in their valence shell
A) He B) Ne C) Ar D) Kr
71. NaCl crystal is made up of
A) NaCl molecules B) Na and Cl atoms C) Na+ and Cl− ions D) Dimers of NaCl
72. The compound that is not ionically bonded is
A) CaCl B) MgCl2 C) BaCl2 D) CH3Cl
73. The maximum number of covalent bonds formed between two atoms never exceeds
A) 1 B) 2 C) 3 D) 4
74. Hybridisation involves
A) Separation of orbitals B) Mixing up of atomic orbitals
C) removal of an electron pair D) Addition of an electron pair
75. Match the following.
Molecule Number of lone pairs on central atom
1) BF3 a) 1
2) H2O b) 0
3) NH3 c) 2
A) 1-a, 2-c, 3-b B) 1-b, 2-c, 3-a C) 1-a, 2-b, 3-c D) 1-c, 2-b, 3-a
76. Which of the following molecules contains a lone pair of electrons on the central atom?
A) H2O B) BeCl2 C) CH4 D) NH3
77. In a double bond connecting two atoms, there is a sharing of
A) 2 electrons B) 3 electrons C) 4 electrons D) 6 electrons
78. In N2 molecule, the atoms are bonded by
A) 81σ, 1π B) 1σ, 2π C) 2σ, 1π D) 2σ, 2π
79. 'π' bond is.......
A) Stronger than σ bond B) Weaker than σ bond
C) Same strength as σ bond D) Un comparable with σ bond
80. Which one is a property of a covalent compound
A) exists as ions B) usually soluble in water
C) conduct electricity D) low melting and boiling points
81. Mention the molecule which show polar covalent bond.
A) NaCl B) C2H6 C) HCl D) MgCl2
82. Overlapping in hydrogen chloride molecule is
A) s − s B) s − p C) p − p D) s − d
83. The atoms in a molecule of hydrogen chloride are held together by
A) Ionic bonds B) Polar covalent bonds
C) Van der waal's forces D) Dipole − Dipole attraction
84. Covalent compounds are soluble in
A) Polar solvents B) Non − polar solvents
C) Concentrated acids D) All solvents
ANSWERS: 1-A; 2-D; 3-B; 4-B; 5-C; 6-D; 7-D; 8-C; 9-A; 10-C; 11-D; 12-D; 13-B; 14-B; 15-C; 16-C; 17-B, 18-C; 19-B; 20-D. 21-A; 22-B; 23-B 24-A; 25-B; 26-C 27-C; 28-A 29-D; 30-A; 31-D; 32-A; 33-C; 34-A 35-A; 36-A; 37-D; 38-B; 39-B; 40-C 41-C; 42-D; 43-D; 44-D; 45-A; 46-C 47-D; 48-D; 49-C; 50-C 51-D; 52-B; 53-D 54-D; 55-C; 56-C; 57-D; 58-D; 59-C 60-A; 61-C; 62-B; 63-A; 64-C; 65-C; 66-C 67-A; 68-D; 69-A; 70-A; 71-C; 72-D; 73-C. 74-B; 75-B; 76-D; 77-C; 78-B. 79-B; 80-D; 81-C; 82-B; 83-B; 84-B.
