Chemistry

Chemical Bonding and Molecular Structure

1,420 Questions

This section tests your knowledge of chemical bonding, molecular structure, and hybridization. It covers ionic and covalent bonds, octet rule exceptions, and molecular geometry. These chemistry questions are common in various competitive entrance examinations.

Ionic and covalent bondsHybridisation of elementsOctet rule exceptionsMolecular geometryIntermolecular forces

Chemical Bonding and Molecular Structure Questions

Multiple choice

Which of the following molecules/ions do not have linear geometry?

  1. NO2-

  2. XeF2

  3. CdI2

  4. CO

  5. PbCl2
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The nitronium ion or sometimes the nitryl ion NO2+ is a generally reactive cation created by the removal of an electron from the paramagnetic nitrogen dioxide molecule. In [O = N = O]+ nitrogen atom has sp hybridisation and thus it is linear in shape. In NO2- the nitrogen atom has sp2 hybridisation and bent shape.

Multiple choice

Which of the following statements is/are false? P. XeCl2 has three lone pairs of electrons with bent geometry. Q. The shape of XeF6 is distorted pentagonal bipyramidal. R. ICl4- and XeF4 both species have identical geometry.

  1. Only P.

  2. Only Q.

  3. Only R.

  4. Only Pand Q.

  5. Only Q and R.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

P. XeCl2 has three lone pairs of electrons with linear geometry. Q. XeF6 has six bond pairs of electrons and one lone pair of electrons with distorted pentagonal bipyramidal shape. R. ICl4- ion and XeF4 molecule has four bond pairs of electrons and two lone pair of electrons with square planar geometry. Hence, only the statement P is false.

Multiple choice

Which of the following molecules/ions has/have sp3d hybridisation and seesaw geometry? P. SF4
Q. XeO2F2
R. XeOF2
S. XeO3F2

  1. Only P

  2. Only P and Q

  3. Only Q and R

  4. Only R and S

  5. Only S
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

SF4 and XeO2F2 have sp3d hybridisation and one lone pair of electrons with seesaw geometry. XeOF2 has sp3d hybridisation and two lone pairs of electrons with T-shaped geometry. XeO3F2 has sp3d hybridisation and zero lone pair of electrons with trigonal bipyramidal geometry.

Multiple choice

Which of the following statements is/are false? P. The central atom in POCl3 has sp3 hybridisation tetrahedral geometry. Q. The number of F-Br-F bond angle equal to 90 degrees in BrF5 is one. R. XeF5+ and ICl4- have identical hybridisation, but do not have similar shape.

  1. Only P.

  2. Only Q.

  3. Only R.

  4. Only P and Q.

  5. Only Q and R.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 Based on VSEPR theory BrF5 has one lone pair of electrons and sp3d2 hybridisation with square pyramidal geometry. The bond angle in F-Br-F is 84.8 degrees.    Hence, statement Q is false.

Multiple choice

Which of the following ions have identical geometry? (i) NH4+, (ii) IF4+, (iii) ClO2-, (iv) ClO4

  1. Only i and ii.

  2. ii and iii.

  3. Only i and iv

  4. Only i, ii and iii.

  5. Only ii, iii and iv.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

NH4+ and ClO4- both ions have four bond pairs of electrons and zero lone pairs of electrons with tetrahedral geometry. IF4+ has four bond pairs of electrons and one lone pair of electrons with seasaw geometry. ClO2- has three bond pairs of electrons and two lone pairs of electrons with V-shaped geometry. Hence, i and iv are identical in geometry.

Multiple choice

Which of the following statements is/are false? (P) SeO32- has pyramidal geometry. (Q) Cl2O molecule has two lone pairs of electrons and bent shape. (R) XeF2 and [I(CN)2]- have sp3d and three lone pairs of electrons with linear and bent geometry.

  1. Only P

  2. Only Q

  3. Only R

  4. Only P and Q

  5. Only Q and R
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Both XeF2 and [I(CN)2]- have sp3d and three lone pairs of electrons with linear geometry. Hence, statement R is false.

Multiple choice

Which of the following molecules bears one lone pair and possesses bent shape?

  1. CCl2

  2. OF2

  3. H2O

  4. HgCl2

  5. O3
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The molecules having two bond pairs and one lone pairs of electrons with bent shape are- O3, SO2, CCl2, etc. The molecules having two bond pairs and two lone pairs of electrons with bent shape are- H2O, OF2, etc. The molecules having two bond pairs and zero lone pairs of electrons with linear shape are- BeCl2, HgCl2, CO2, etc.

Multiple choice

Which of the following statements is/are incorrect? (P) I3- is linear shaped and XeCl2 possesses V-shaped geometry. (Q) BF3 and SO3 have same number of bond pairs and lone pairs with identical geometry. (R) XeOF4 molecule has square pyramidal shape.

  1. Only P.

  2. Only Q.

  3. Only R.

  4. Only P and Q.

  5. Only Q and R.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

(P) The molecules/ions having two bond pairs and three lone pairs with linear geometry are- XeF2, I3-, XeCl2, etc. (Q) BF3 and SO3 have three bond pairs and zero lone pairs with identical geometry, trigonal planar. (R) XeOF4 molecule has 5 bond pairs and one lone pair with square pyramidal shape. Hence, statement P is only incorrect.

Multiple choice

Which of the following statements regarding the 1, 3-butadiene is/are false? A. The hybridisation of Carbon atom number 1 and 4 is sp2. B. The single bond between carbon atom number 2 and 3 is of the same length as the C-C bond length in ethane. C. 1, 3-butadiene is a conjugated diene.

  1. Only A

  2. Only B

  3. Only C

  4. Only B and C

  5. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Due to resonance C2-C3 bond has some double bond character, and hence its bond length (1.46 Ǻ) is shorter than the C-C bond length in ethane (1.54 Ǻ). Thus this option is correct.

Multiple choice

Which of the following compounds/molecules has dipole moment?

  1. HCl

  2. CO2 gas

  3. CH4

  4. N2
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

HCl molecules, have a dipole moment because the hydrogen atom has a slight positive charge and the chlorine atom has a slight negative charge. Because of the force of attraction between oppositely charged particles, there is a small dipole-dipole force of attraction between adjacent HCl molecules.

Multiple choice

Which halogen is a rare halogen?

  1. F

  2. Cl

  3. Br

  4. At
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The halogens are all chemically active. For that reason, none occur naturally in the form of elements. However—with the exception of astatine—they are very widespread and abundant in chemical compounds. Astatine is radioactive and is one of the rarest of the chemical elements. Astatine is generally regarded as one of the rarest naturally occurring elements. According to some estimates, no more than 44 milligrams of the element are to be found in Earth's crust.

Multiple choice

Which of the following hybridisations leads to regular tetrahedral structure?

  1. 'sp' hybridisation

  2. sp2 hybridisation

  3. sp3 hybridisation

  4. sp3d2 hybridisation
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In this hybridisation, one '2s' and three '2p' orbitals present in the valence shell of the excited carbon atom get hybridised to give rise to four new orbitals of equivalent energies. Each sp3 hybrid orbital is an average of one '2s' orbital and three '2p' orbitals having one fourth 's' character and three fourth 'p' character.