Q.1 Which of the following molecules has a trigonal planar geometry?
CH4
BF3
NH3
H2O
Explanation - BF3 has three bonding pairs and no lone pairs on the central atom, giving it a trigonal planar geometry.
Correct answer is: BF3
Q.2 Which type of hybridization is present in the carbon atoms of ethyne (C2H2)?
sp
sp2
sp3
sp3d
Explanation - In ethyne, each carbon atom forms two sigma bonds and two pi bonds, corresponding to sp hybridization.
Correct answer is: sp
Q.3 The bond angle in water (H2O) is approximately:
104.5°
109.5°
120°
180°
Explanation - Water has a bent shape due to two lone pairs on oxygen, reducing the H-O-H bond angle from 109.5° to about 104.5°.
Correct answer is: 104.5°
Q.4 Which of the following compounds exhibits hydrogen bonding?
CH4
NH3
CCl4
CO2
Explanation - NH3 has N-H bonds and a lone pair on nitrogen, allowing hydrogen bonding to occur.
Correct answer is: NH3
Q.5 The bond order of the O2 molecule is:
1
2
3
0
Explanation - According to molecular orbital theory, O2 has 8 bonding electrons and 4 antibonding electrons, giving bond order = (8-4)/2 = 2.
Correct answer is: 2
Q.6 Which of the following is a polar molecule?
CO2
CH4
NH3
CCl4
Explanation - NH3 is trigonal pyramidal and asymmetric, resulting in a net dipole moment, making it polar.
Correct answer is: NH3
Q.7 Which type of bond is present in NaCl?
Covalent
Ionic
Metallic
Coordinate
Explanation - NaCl is formed by the transfer of an electron from sodium to chlorine, creating an ionic bond.
Correct answer is: Ionic
Q.8 Which molecule has a linear shape?
CO2
NH3
H2O
CH4
Explanation - CO2 has two double bonds and no lone pairs on the central carbon, resulting in a linear geometry.
Correct answer is: CO2
Q.9 Which of the following compounds has sp3 hybridized carbon atoms?
C2H2
CH4
C2H4
HCN
Explanation - In CH4, the carbon forms four sigma bonds, corresponding to sp3 hybridization.
Correct answer is: CH4
Q.10 Which molecule exhibits resonance?
H2O
O3
CH4
NH3
Explanation - Ozone (O3) has delocalized electrons over the three oxygen atoms, showing resonance.
Correct answer is: O3
Q.11 Which of the following elements forms a double bond with oxygen?
Na
C
H
Cl
Explanation - Carbon can form double bonds with oxygen, as seen in CO and CO2.
Correct answer is: C
Q.12 What is the shape of the SF6 molecule?
Octahedral
Tetrahedral
Trigonal planar
Linear
Explanation - SF6 has six bonding pairs around sulfur with no lone pairs, resulting in an octahedral shape.
Correct answer is: Octahedral
Q.13 Which of the following has the highest electronegativity?
Na
Cl
Mg
Al
Explanation - Chlorine is highly electronegative due to its high nuclear charge and small size.
Correct answer is: Cl
Q.14 Which molecule has a bent shape?
CO2
SO2
CH4
BF3
Explanation - SO2 has two bonding pairs and one lone pair on sulfur, giving it a bent shape.
Correct answer is: SO2
Q.15 The bond in HCl is:
Nonpolar covalent
Polar covalent
Ionic
Metallic
Explanation - HCl has unequal sharing of electrons due to the difference in electronegativity between H and Cl, resulting in a polar covalent bond.
Correct answer is: Polar covalent
Q.16 Which of the following is a coordinate covalent bond?
NH4+
H2
O2
CH4
Explanation - In NH4+, the nitrogen donates a lone pair to form a bond with H+, making it a coordinate covalent bond.
Correct answer is: NH4+
Q.17 Which of the following molecules is nonpolar despite having polar bonds?
CO2
H2O
NH3
HF
Explanation - CO2 has a linear shape, so the bond dipoles cancel each other, making the molecule nonpolar.
Correct answer is: CO2
Q.18 The hybridization of the central atom in PCl5 is:
sp3
sp3d
sp3d2
sp2
Explanation - Phosphorus in PCl5 has five bonding pairs and no lone pairs, corresponding to sp3d hybridization.
Correct answer is: sp3d
Q.19 Which of the following molecules has a tetrahedral geometry?
CH4
NH3
H2O
CO2
Explanation - CH4 has four bonding pairs and no lone pairs, giving it a tetrahedral shape.
Correct answer is: CH4
Q.20 The bond angle in ammonia (NH3) is approximately:
107°
109.5°
104.5°
120°
Explanation - NH3 has a trigonal pyramidal shape due to one lone pair, reducing the bond angle from 109.5° to about 107°.
Correct answer is: 107°
Q.21 Which molecule has delocalized π electrons?
Benzene
Methane
Ethane
Ammonia
Explanation - Benzene has alternating double bonds with delocalized π electrons over the ring.
Correct answer is: Benzene
Q.22 Which of the following is a metallic bond?
NaCl
Fe
H2O
CO2
Explanation - In metallic bonds, valence electrons are delocalized over metal atoms, as in Fe.
Correct answer is: Fe
Q.23 Which is the correct order of increasing bond length?
C-C < C=C < C≡C
C≡C < C=C < C-C
C=C < C-C < C≡C
C-C < C≡C < C=C
Explanation - Triple bonds are shorter than double bonds, which are shorter than single bonds.
Correct answer is: C≡C < C=C < C-C
Q.24 Which of the following molecules is polar?
CH4
CCl4
H2O
CO2
Explanation - H2O is bent and has a net dipole moment, making it polar.
Correct answer is: H2O
Q.25 Which molecule has sp2 hybridization at the central atom?
BF3
CH4
C2H2
NH3
Explanation - Boron in BF3 forms three sigma bonds and has no lone pair, corresponding to sp2 hybridization.
Correct answer is: BF3