Q.1
What type of hybridization is possible in square planar molecules? [ Pb CET 1991]
  • a)sp3d
  • b) dsp3
  • c)dsp2
  • d)sp3d2
Q.2
NH3 has a much higher boiling point that PH3 because ... [ MLNR 1994]
  • a) NH3 has larger molecular weight
  • b) NH3 undergoes umbrella inversion
  • c) NH3 forms hydrogen bond
  • d) NH3 contains ionic bonds whereas PH3 contains covalent bonds
Q.3
The complex ion [Co(NH3)6]3+ is formed by sp3d2 hybridization. Hence the ion should posses ... [ CBSE PMT 1990]
  • a) Octahedral geometry
  • b) tetrahedral geometry
  • c)square planar geometry
  • d)tetragonal geometry
Q.4
Which of the following is the correct order of interactions? [ CBSE PMT 1993]
  • a) Covalent < hydrogen bonding < van der Waals < dipole - dipole
  • b) van der Waals < hydrogen bonding < dipole - dipole < Covalent
  • c)van der Waals
  • d)dipole - dipole < van der Waals
Q.5
Which type of bond is not present in HNO2 molecule .. [ Roorkee Screen Test 1991]
  • a)Covalent
  • b) Co-ordinate
  • c)Ionic
  • d)Ionic as well as co-ordinate
Q.6
Which of the following will have low heat of fusion? [ DEC 1994]
  • a) covalent solid
  • b) metallic solid
  • c)an ionic solid
  • d)a molecular solid
Q.7
In allene structure three carbon atoms are joined by ... [ BHYU 1993]
  • a) three sigma bonds and three pi-bonds
  • b) Two sigma bonds and one pi-bond
  • c)Two sigma bonds and two pi bonds
  • d)three pi bonds only
Q.8
Intermolecular forces in solid hydrogen are ... [ Pb CET 1991]
  • a)van der Waal's forces
  • b) Covalent forces
  • c)Hydrogen bonds
  • d)None of these
Q.9
Among LiCl, BeCl2, BCl3 and CCl4 the covalent bond character follows the order ... [ CBSE PMT 1990]
  • a) LiCl < BeCl2 > BCl3 > CCl4
  • b) LiCl > BeCl2 < BCl3 < CCl4
  • c) LiCl < BeCl2 < BCl3 < CCl4
  • d) LiCl > BeCl2 >BCl3 > CCl4
Q.10
The central atom assumes sp3 hybridization in ... [ MLNR 1994]
  • a) PCl3
  • b) SO3
  • c)BF3
  • d)NO3-
Q.11
Strongest hydrogen bond is shown by ... [ CBSE PMT 1992]
  • a)Water
  • b) Ammonia
  • c)Hydrogen fluoride
  • d)Hydrogen sulphide
Q.12
Mark the incorrect statement in the following ... [ CBSE PMT 1994]
  • a) the bond order in the species O2, O2+ and O2- decreases as O2+ > O2 > O2-
  • b)The bond energy in a diamatic molecule always increases when an electron in lost
  • c)Electrons in antibonding M.O> contribute to repulsion between two atoms
  • d)With increase in bond order, bond length decreases and bond strength increases
Q.13
Linear combination of two hybridized orbitals belonging to two atoms and each having one electron leads to a .. [ CBSE PMT 1990]
  • a) Sigma bond
  • b) Double bond
  • c) Co-ordinate covalent bond
  • d) pi- bond
Q.14
Elements have electronegativities 1.2 and 3.0 bond formed between them would be ...{CPMT 1994]
  • a) Ionic
  • b) Covalent
  • c)Co-ordinate
  • d)Metallic
Q.15
Which of the following does not exhibit paramagnetism? [ BHU 1993]
  • a) NO
  • b) NO2
  • c)ClO2
  • d)ClO2-
Q.16
The element having electron configuration 1s2, 2s2, 2p6, 3s2, 3p3 is [ CPMT 1991]
  • a)Only trivalent
  • b) Only tetravalent
  • c)Only pentavalent
  • d)tetravalent and pentavalent
Q.17
Which of the following properties would suggest that a compound under investigation is covalent? [ pb. CET 1990]
  • a) It conducts electricity on melting
  • b) It is a non-electrolyte
  • c) It has a high melting point
  • d) It is a compound of metal and non metal
Q.18
The dielectric constant of H2O isthe electrostatic force of attraction between Na+ and Cl- will be .... [ CBSE PMT 1994]
  • a) reduced to 1/40 in water than in air
  • b) reduced to 1/80 in water than in air
  • c)will be increased to 80 in water than in air
  • d)will remain unchanged
Q.19
Two lone pairs of electrons and two bonded pairs of electrons are present in ... [ CPMT 1993]
  • a) NH3
  • b) BF3
  • c)H2O
  • d)CO2
Q.20
Which one of the following is paramagnetic? [ CPMT 1992]
  • a)NO+
  • b) O2-
  • c)CN-
  • d)CO
Q.21
Which one shows maximum hydrogen bonding? [ CBSE PMT 1990]
  • a) H2O
  • b) H2Se
  • c) H2S
  • d) HF
Q.22
Which of the following structures is expected to have three bond pairs and one loan pair? [ JIPMER 1994]
  • a) tetrahedral
  • b) trigonal planar
  • c)pyramidal
  • d)octahedral
Q.23
The percentage of s-character in the hybrid orbitals sp, sp2 and sp3 follows the pattern... [ AIIMS 1993]
  • a) sp3 > sp2 > sp
  • b) sp > sp2 > sp3
  • c)sp=sp2 > sp3
  • d)sp=sp2=sp3
Q.24
In compound X, all the bond angles are exactly 109°28'. X is
  • a)Chloromethane
  • b) Carbon tetrachloride
  • c)Iodoform
  • d)Chloroform
Q.25
According to molecular orbital theory, O2+ possesses ... [ Pb CET 1989]
  • a) Bond order of 2.5
  • b) Three unpaired electrons
  • c) Diamagnetic character
  • d) Stability lower than O2
Q.26
Which of the following has a net dipole moment? [ harayana CEET 1994]
  • a) CCl4
  • b) BF3
  • c)NH3
  • d)CO2
Q.27
The distribution of electrons in the molecular orbital of O2 molecule is as follows... [ ISM 1994] σ1s2,σ*1s2σ2s2,σ*2s2σ2pz2
  • a) π2px2 ,π2py2π*2px2 ,π*2py0
  • b)π2px2 ,π2py2π*2px1 ,π*2py1
  • c)π2px2 ,π2py1π*2px1 ,π*2py2
  • d)π2px2 ,π2py0π*2px2 ,π*2py2
Q.28
Both sp2 and sp3 hybrid carbon are present in which one of the following compounds? [ CPMT 1992]
  • a)CH3 - CH3
  • b) CH2=CH2
  • c)CH Ξ CH
  • d)CH3 -CH=CH - CH3
Q.29
in an anion HCOO- the two carbon-oxygen bonds are found to be of equal length. What is the reason for it? [ AIEEE 2003]
  • a) Electronic orbitals of carbon atom are hybridize
  • b) The C=O bond is weaker than C-O bond
  • c) The anion HCOO- has two resonating structures
  • d) The anion is obtained by removal of proton from the acid molecule
Q.30
hich as minimum bond angle? [ Pb CET 1986]
  • a) H2O
  • b) H2S
  • c)NH3
  • d)CH4
0 h : 0 m : 1 s