JEE Chemistry Chemical Bonding and Molecular Structure MCQs Set A

Question. The attractive force which holds various constituents (atoms, ions etc.) together in different chemical species is called a
(a) chemical bond
(b) ionic bond
(c) chemical compound
(d) covalent bond

Answer: A

Question. The evolution of various theories of valence and the interpretation of the nature of chemical bonds have closely been related to the developments in the understanding of
(a) All of the above
(b) periodic table
(c) electronic configuration of elements
(d) structure of atom

Answer: A

Question. In the formation of a molecule which of the following take part in chemical combination?
(a) valence electron
(b) cation
(c) anion
(d) inner shell electron

Answer: A

Question. The bond formed as a result of the electrostatic attraction between the positive and negative ions is termed as
(a) Electrovalent bond
(b) Covalent bond
(c) Chemical bond
(d) Co-ordinate bond

Answer: A

Question. Cation and anion combines in a crystal to form following type of compound
(a) ionic
(b) metallic
(c) dipole-dipole
(d) covalent

Answer: A

Question. Electrovalence of calcium and chlorine respectively is
(a) + 2, – 1
(b) + 1, – 2
(c) + 1, – 1
(d) + 2, – 2

Answer: A

Question. When a metal atom combines with non-metal atom, the non-metal atom will
(a) gain electrons and increase in size
(b) lose electrons and increase in size
(c) lose electrons and decrease in size
(d) None of these

Answer: A

Question. Who introduced the term covalent bond ?
(a) Langmuir
(b) Heitler and London
(c) Lewis
(d) Nyholm and Gillespie

Answer: A

Question. Which of the following is/are not the condition(s) for Lewis dot structure?
(i) Each bond is formed as a result of sharing of an electron pair between the atoms.
(ii) From the two combining atoms only one atom contribute electron(s) to the shared pair.
(iii) The combining atoms attain the outer shell noble gas configurations as a result of the sharing of electrons.
(a) (ii) only
(b) (i) and (iii)
(c) (ii) and (iii)
(d) (iii) only

Answer: A

Question. In N₂ molecule, the number of electrons shared by each nitrogen atom is
(a) 3
(b) 1
(c) 2
(d) 5

Answer: A

Question. The lowest energy structure is the one with the _____ formal charges on the atoms.
(a) smallest
(b) highest
(c) negative
(d) zero

Answer: A

Question. In the cyanide ion, the formal negative charge is on
(a) N
(b) C
(c) Resonate between
(d) All of these

Answer: A

Question. What are the exceptions of the octet rule ?
(a) All of these
(b) Expanded octet of the central atom
(c) An odd number of electrons on central atom
(d) The incomplete octet of central atom

Answer: A

Question. In which of the following molecules octet rule is not followed?
(a) NO
(b) CH₄
(c) NH₃
(d) CO₂

Answer: A

Question. Among the following the electron deficient compound is
(a) BCl₃
(b) CCl₄
(c) BeCl₂
(d) PCl₅

Answer: A

Question. Complete the following statement by choosing theappropriate option. Ionic bonds will be formed more easily between elements with comparatively A and elements with comparatively high negative value of B .
a) A = low ionization enthalpy
B = electron gain enthalpy
b) A = high ionization enthalpy
B = electron gain enthalpy
c) A = low electronegativity
B = ionization enthalpy
d) A = high electronegativity
B = ionization enthalpy

Answer: A

Question. In ionic solids how crystal structure get stabilized
(a) By the energy released in the formation of crystal lattice
(b) By achieving octet of electrons around the ionic species in gaseous state
(c) By electron gain enthalpy and the ionization enthalpy
(d) None of these

Answer: A

Question. Energy required to completely separate one mole of a solid ionic compound into gaseous constituent ions is called
(a) Lattice enthalpy
(b) Bond dissociation enthalpy
(c) Electron gain enthalpy
(d) Ionisation enthalpy

Answer: A

Question. The effect of more electronegative atom on the strength of ionic bond
(a) increases
(b) decreases
(c) decreases slowly
(d) remains the same

Answer: A

Question. Among the following which compound will show the highest lattice energy ?
(a) NaF
(b) RbF
(d) KF

Answer: A

Question. Which of the following bond will have highest ionic character?
(a) H–F
(b) H–Br
(c) H–I
(d) H–Cl

Answer: A

Question. Which of the following pairs will form the most stable ionic bond ?
(a) Mg and F
(b) Na and F
(c) Na and Cl
(d) Li and F

Answer: A

Question. Which of the following methods is used for measuring bond length ?
(a) All of these
(b) Spectroscopic techniques
(c) Electron-diffraction
(d) X-ray diffraction

Answer: A

Question. _______ is measured as the radius of an atom’s core which is in contact with the core of an adjacent atom in a bonded situation
(a) Covalent radius
(b) Ionic radius
(c) Bond length
(d) van der Waal’s radius

Answer: A

Question. Which of the following statement is correct?
(a) All of these
(b) Larger the bond dissociation enthalpy, stronger will be the bond in the molecule
(c) The unit of bond enthalpy is kJ mol^–1
(d) Amount of energy required to break one mole of bonds of a particular type between two atoms in a gaseous state is called bond enthalpy.

Answer: A

Question. Which of the following is/are misconception(s) associated with resonance ?
(i) The molecule exist for a certain fraction of time in one cannonical form and for other fractions of time in other cannonical forms.
(ii) The cannonical forms have no real existence.
(iii) There is no such equilibrium between the cannonical forms.
(a) (i) only
(b) (i) and (iii)
(c) (ii) and (iii)
(d) (iii) only

Answer: A

Question. All the bond lengths of sulphur – oxygen in sulphate ion, are equal because of
(a) resonance
(b) symmetry
(c) high electronegativity of oxygen
(d) None of these

Answer: A

Question. Resonance is due to
(a) delocalization of pi electrons
(b) delocalization of sigma electrons
(c) migration of protons
(d) None of these

Answer: A

Question. The molecule which has zero dipole moment is
(a) BF₃
(b) NF₃
(c) ClO₂
(d) None of these

Answer: A

Question. Which of the following has dipole moment?
(a) NH₃
(b) CO₂
(c) CH₄
(d) None of these

Answer: A

Question. Identify the non polar molecule in the following compounds
(a) H₂
(b) HCl
(c) HBr
(d) HF and HBr

Answer: A

Question. A neutral molecule XF₃ has a zero dipole moment. The element X is most likely
(a) boron
(b) carbon
(c) chlorine
(d) nitrogen

Answer: A

Question.  Among the following, the molecule of high dipole moment is
(a) H₂O
(b) CCl₄
(c)   NH₃
(d) CHCl₃

Answer: A

Question. Which one of the following molecules is expected to have zero dipole moment?
(a) CO₂
(b) CaF₂
(c) H₂O
(d) SO₂

Answer: A

Question. The most polar bond is
(a) C – F
(b) C – Br
(c) C – O
(d) C – S

Answer: A

Question. According to Fajan’s rule, covalent bond is favoured by
(a) Small cation and large anion
(b) Small cation and small anion
(c) Large cation and large anion
(d) Large cation and small anion

Answer: A

Question. Which of the following salt shows maximum covalent character?
(a) AlCl₃
(b) None of these
(c) MgCl₂
(d) LaCl₃

Answer: A

Question. The covalent bond length is the shortest in which one of the following bonds?
(a) O — H
(b) C — C
(c) C — O
(d) None of these

Answer: A

Question. Hydrogen chloride molecule contains
(a) polar covalent bond
(b) co-ordinate bond
(c) double bond
(d) electrovalent bond

Answer: A

Question. Sodium chloride is an ionic compound whereas hydrogen chloride is mainly covalent because
(a) hydrogen is non-metal
(b) hydrogen chloride is a gas
(c) sodium is less reactive
(d) electronegativity difference in the case of hydrogen and chlorine is less than 2.1

Answer: A

Question. According to VSEPR theory the geometry of a covalent molecules depends upon
(a) All the above
(b) the number of electron pairs present in the outer shell of the central atom
(c) the number of lone pairs of electrons
(d) the number of bond pairs of electrons

Answer: A

Question. In BrF₃ molecule, the lone pairs occupy equatorial positions to minimize
(a) lone pair - lone pair repulsion and lone pair - bond pair repulsion
(b) lone pair - lone pair repulsion only
(c) bond pair - bond pair repulsion only
(d) lone pair - bond pair repulsion only

Answer: A

Question. The number of lone pair and bond pair of electrons on the sulphur atom in sulphur dioxide molecule are respectively
(a) 1 and 4
(b) 4 and 1
(c) 1 and 3
(d) 3 and 1

Answer: A

Question. A molecule has two lone pairs and two bond pairs around the central atom. The molecule shape is expected to be
(a) V-shaped
(b) linear
(c) triangular
(d) tetrahedral

Answer: A

Question. Using VSEPR theory, predict the species which has square pyramidal shape
(a) BrF₅
(b) CCl₄
(c) SnCl₂
(d) SO₃

Answer: A

Question. Among the following molecules : SO₂, SF₄, CIF₃, BrF₅ and XeF₄, which of the following shapes does not describe any of the molecules mentioned?
(a) Trigonal bipyramidal
(b) T-shape
(c) Bent
(d) See-saw

Answer: A

Question. Shape of methane molecule is
(a) tetrahedral
(b) pyramidal
(c) square planar
(d) octahedral

Answer: A

Question. The shape of stannous chloride molecule is
(a) bent
(b) square planar
(c) see-saw
(d) trigonal pyramidal

Answer: A

Question. Which of the following statements is false ?
(a) Acetylene molecule has three pi bonds and three sigma bonds
(b) Water molecule has two sigma bonds and two lone pairs
(c) HCl molecule has one sigma bond
(d) None of these

Answer: A

Question. Allyl cyanide molecule contains
(a) 9 sigma bonds, 3 pi bonds and one lone pair
(b) 9 sigma bonds, 4 pi bonds and no lone pair
(c) 8 sigma bonds, 5 pi bonds and one lone pair
(d) 8 sigma bonds, 3 pi bonds and two lone pairs

Answer: A

Question. The enolic form of a acetone contains
(a) 9 sigma bonds, 1 pi bond and 2 lone pairs
(b) 8 sigma bonds, 2 pi bonds and 2 lone pairs
(c) 10 sigma bonds, 1 pi bond and 1 lone pair
(d) 9 sigma bonds, 2 pi bonds and 1 lone pair

Answer: A

Question. The angle between the overlapping of one s-orbital and one p-orbital is
(a) 180°
(b) 120°
(c) 120° 60'
(d) None of these

Answer: A

Question. Linear combination of two hybridized orbitals belonging to two atoms and each having one electron leads to a
(a) sigma bond
(b) double bond
(c) co-ordinate covalent bond
(d) pi bond

Answer: A

Question. Which of the following is/are not essential condition(s) for hybridisation?
(i) The orbitals present in the valence shell of the atom are hybridised.
(ii) The orbitals undergoing hybridisation should have almost equal energy.
(iii) Promotion of electron is essential prior to hybridisation.
(iv) Only half filled orbitals participate in hybridisation.
(a) (iii) and (iv)
(b) (iii) only
(c) (i) only
(d) (iv) only

Answer: A

Question. As the s-character of hybridised orbital increases, the bond angle
(a) increase
(b) becomes zero
(c) does not change
(d) decrease

Answer: A

Question.  The nature of hybridisation in the ammonia molecule is
(a) sp³
(b) dp²
(c) sp²
(d) sp

Answer: A

Question. The shape of sulphate ion is
(a) tetrahedral
(b) triagonal
(c) square planar
(d) trigonal planar

Answer: A

Question. The strength of bonds formed by s–s and p–p, s–p overlap in the order of
(a) s–s > s–p > p–p
(b) p–p > s–s > s–p
(c) s–p > s–s > p–p
(d) s–s > p–p > s–p

Answer: A

Question. The shape of CO₂ molecule is
(a) linear
(b) planar
(c) pyramidal
(d) tetrahedral

Answer: A