🧪 Chemistry · Class 11 · NEET & JEE
Chemical Bonding and Molecular Structure - Practice Questions with Answers 75 free MCQs on Chemical Bonding and Molecular Structure, each with its own worked answer and explanation. Understand how atoms join to form molecules. Covers ionic and covalent bonding, VSEPR theory, hybridization (sp, sp², sp³), molecular orbital theory, bond polarity, and intermolecular forces like hydrogen bonding.
Take the timed Chemical Bonding and Molecular Structure chapterwise test → 75 practice questions on Chemical Bonding and Molecular Structure , sorted Easy → Hard. Try each one first, then open its answer page for the worked explanation. Want the full theory first? Read the Chemical Bonding and Molecular Structure notes .
Linear 180 deg, e.g. CO2 Trigonal Planar 120 deg, e.g. BF3 Tetrahedral 109.5 deg, e.g. CH4 Trigonal Bipyramidal e.g. PCl5 Octahedral e.g. SF6 VSEPR theory predicts molecular shape from the number of bonding and lone electron pairs around the central atom.
Easy - 25 questions Q1.
Which of the following substances is expected to have the highest melting point?
A NaClB CO<sub>2</sub> (dry ice)C I<sub>2</sub>D CH<sub>4</sub>Show answer & explanation →
Q2.
Which of the following molecules is non-polar despite containing polar bonds?
A NH<sub>3</sub>B BF<sub>3</sub>C H<sub>2</sub>OD HClShow answer & explanation →
Q4.
A molecule in which the central atom is sp<sup>2</sup> hybridised with no lone pairs has a bond angle of:
A 90 degreesB 109.5 degreesC 104.5 degreesD 120 degreesShow answer & explanation →
Q5.
Among carbon-carbon single, double and triple bonds, the shortest and strongest is the:
A triple bondB double bondC single bondD they are all equalShow answer & explanation →
Q6.
A covalent bond is formed by:
A Sharing of electrons between atomsB Transfer of electrons under most conditions encounteredC Electrostatic attraction as frequently observed in practiceD Metallic bonding in many documented casesShow answer & explanation →
Q7.
An ionic bond is formed by:
A Transfer of electrons from metal to non-metalB Mutual sharing of electron pairs between two non-metalsC Delocalised metallic bonding throughout a metal latticeD Weak hydrogen bonding between electronegative atomsShow answer & explanation →
Q8.
Lewis dot structure represents:
A Valence electrons as dots around the symbolB Every single electron present in the entire atomC Electrons located within the nucleus itselfD Neutrons present in the atomic nucleusShow answer & explanation →
Q9.
How many bonding pairs are in a double bond?
A Two pairs (4 electrons)B One pair according to conventional understandingC Three pairs in routine practiceD Zero overall in most casesShow answer & explanation →
Q15.
A sigma bond is formed by:
A Head-on (axial) overlap of orbitalsB Lateral (side) overlap under typical conditionsC Ionic transfer according to standard textbooksD Metallic orbital in general practiceShow answer & explanation →
Q16.
A pi bond is formed by:
A Lateral (sideways) overlap of p orbitalsB Direct head-on overlap of two p orbitals along the bond axisC Complete transfer of electrons between two bonded atomsD Overlap of two spherical s orbitals along the bond axisShow answer & explanation →
Q18.
Electronegativity difference greater than 1.7 generally indicates:
A Ionic bondB Covalent bondC Metallic bondD Coordinate bondShow answer & explanation →
Q19.
In a coordinate (dative) bond, both electrons are donated by:
A One atom (the donor/Lewis base)B Both atoms as frequently describedC The solvent in most textbook accountsD An outside source during normal conditionsShow answer & explanation →
Q23.
Hydrogen bonding is possible only when hydrogen is bonded to:
A Highly electronegative atom with lone pair (F, O, N)B A carbon atom in a saturated hydrocarbon chainC Any non-metal element regardless of electronegativityD An atom from the noble gas familyShow answer & explanation →
Q25.
The octet rule states that atoms tend to:
A Have 8 electrons in their valence shellB Possess exactly 8 protons in the nucleusC Form exactly 8 covalent bonds with neighbouring atomsD Gain a full 8 additional electrons regardless of starting countShow answer & explanation →
Medium - 25 questions Q26.
The hybridisation of the sulfur atom in the SF<sub>4</sub> molecule is:
A sp<sup>3</sup>B sp<sup>3</sup>dC sp<sup>2</sup>D sp<sup>3</sup>d<sup>2</sup>Show answer & explanation →
Q27.
According to VSEPR theory, the molecular shape of ClF<sub>3</sub> is:
A Trigonal planarB Trigonal pyramidalC T-shapedD BentShow answer & explanation →
Q29.
A molecule of ethene, C<sub>2</sub>H<sub>4</sub>, contains how many sigma and pi bonds respectively?
A 5 sigma and 1 piB 4 sigma and 2 piC 6 sigma and 0 piD 3 sigma and 2 piShow answer & explanation →
Q30.
The correct decreasing order of bond angle among CH<sub>4</sub>, NH<sub>3</sub> and H<sub>2</sub>O is:
A H<sub>2</sub>O > NH<sub>3</sub> > CH<sub>4</sub>B CH<sub>4</sub> > NH<sub>3</sub> > H<sub>2</sub>OC NH<sub>3</sub> > CH<sub>4</sub> > H<sub>2</sub>OD CH<sub>4</sub> > H<sub>2</sub>O > NH<sub>3</sub>Show answer & explanation →
Q31.
The hybridisation of carbon in ethyne (acetylene) is:
A spB sp<sup>2</sup>C sp<sup>3</sup>D sp<sup>3</sup>dShow answer & explanation →
Q34.
PCl<sub>5</sub> has which hybridisation?
A sp<sup>3</sup>dB sp<sup>3</sup>C sp<sup>3</sup>d<sup>2</sup>D sp<sup>2</sup>Show answer & explanation →
Q35.
SF<sub>6</sub> has which hybridisation?
A sp<sup>3</sup>d<sup>2</sup>B sp<sup>3</sup>dC sp<sup>3</sup>D sp<sup>2</sup>Show answer & explanation →
Q36.
According to VSEPR, lone pairs take up more space than bonding pairs because:
A Lone pairs are only on one nucleus and spread more (more repulsion)B Lone pairs simply contain a greater number of electrons overallC Lone pairs are confined entirely within spherical s orbitalsD Lone pairs sit physically closer to the central nucleusShow answer & explanation →
Q39.
Which molecule is paramagnetic according to MO theory?
A O<sub>2</sub>B N<sub>2</sub>C H<sub>2</sub>D F<sub>2</sub>Show answer & explanation →
Q40.
Bent's rule states that:
A Atoms preferentially direct more p character toward electronegative substituentsB All bond angles must equal exactly 109.5 degrees in any molecule in most textbook accountsC Lone pairs usually preferentially occupy equatorial positions mainly during normal conditionsD All hybrid orbitals on an atom remain perfectly equivalent as generally observedShow answer & explanation →
Q41.
Why does water have a higher boiling point than H<sub>2</sub>S?
A Water has strong hydrogen bonds; H<sub>2</sub>S only has weak van der Waals forcesB Water generally has a lower molecular weight than H<sub>2</sub>S in typical laboratory settingsC H<sub>2</sub>S has stronger intramolecular covalent S-H bonds than water under usual circumstancesD Water possesses partial ionic character in its O-H bonds according to most researchersShow answer & explanation →
Q42.
Which of the following is an exception to the octet rule by being electron-deficient?
A BF<sub>3</sub>B PCl<sub>5</sub>C SF<sub>6</sub>D NO<sub>2</sub>Show answer & explanation →
Q43.
Resonance structures differ only in:
A Position of electrons (bonds/lone pairs), not nucleiB The spatial position of the atomic nuclei themselvesC The total number of atoms present in the structureD The overall molecular formula of the compoundShow answer & explanation →
Q44.
The bond length order in a triple bond vs double bond vs single bond is:
A Triple < double < singleB Single < double < tripleC All equalD Double < triple < singleShow answer & explanation →
Q45.
The formal charge of an atom in a Lewis structure is:
A Valence electrons - non-bonding electrons - (bonding electrons/2)B The sum of valence electrons and lone pair electrons presentC The difference between the nuclear charge and the atomic numberD The conventional oxidation state assigned to that atomShow answer & explanation →
Q46.
Fajan's rules predict that a compound has more covalent character when:
A The cation is small and highly charged, and the anion is large and highly chargedB Both the cation and the anion happen to be of nearly identical ionic radiusC The compound has already been independently classified as purely ionicD The surrounding reaction temperature is kept unusually high throughoutShow answer & explanation →
Q47.
Which bond is more polar: H-F or H-Cl?
A H-F (larger electronegativity difference)B H-Cl, due to chlorine's greater atomic radius increasing polarityC Both bonds are equally polar with identical dipole momentsD Neither bond shows any measurable polarity at allShow answer & explanation →
Q48.
The dipole moment of CO<sub>2</sub> is zero because:
A Two equal C=O dipoles point in opposite directions and cancelB There is no electronegativity difference between carbon and oxygenC The carbon atom itself carries no partial charge in any bondD CO<sub>2</sub> exists as a non-polar solid at room temperatureShow answer & explanation →
Q49.
Which type of intermolecular force is present in all molecules?
A London dispersion (van der Waals) forcesB Hydrogen bonding between electronegative atoms and hydrogenC Ionic attraction between fully charged speciesD Dipole-dipole attraction exclusive to polar moleculesShow answer & explanation →
Q50.
The lattice energy of an ionic compound depends on:
A Charges and sizes of ions (higher charge and smaller size = higher lattice energy)B The surrounding ambient temperature alone, independent of any ionic propertyC The total number of electrons present throughout the crystal latticeD The visible colour displayed by the compound under normal lightingShow answer & explanation →
Hard - 25 questions Q51.
The molecular shape of the triiodide ion, I<sub>3</sub><sup>-</sup>, as predicted by VSEPR theory is:
A BentB Trigonal planarC LinearD T-shapedShow answer & explanation →
Q52.
Among the following species, which has the highest bond order?
A O<sub>2</sub>B O<sub>2</sub><sup>-</sup>C O<sub>2</sub><sup>2-</sup>D O<sub>2</sub><sup>+</sup>Show answer & explanation →
Q53.
According to molecular orbital theory, the number of unpaired electrons present in a molecule of O<sub>2</sub> is:
Show answer & explanation →
Q55.
The measured dipole moment of HCl is 1.03 D, while the value calculated for 100% ionic character is 6.12 D. The percent ionic character of the H-Cl bond is about:
Show answer & explanation →
Q56.
In MO theory, bonding MOs are formed by:
A Constructive interference of atomic wavefunctionsB Destructive interference between two atomic orbital wavefunctionsC Overlap restricted exclusively to spherical s orbitalsD An arbitrary, unguided combination of orbitalsShow answer & explanation →
Q57.
The HOMO of H<sub>2</sub> is the:
A Sigma 1s bonding MO (filled)B Sigma* 1s antibonding MOC 1s atomic orbitalD 2s orbitalShow answer & explanation →
Q58.
Why is the bond angle in water (104.5°) less than in NH<sub>3</sub> (107°)?
A Water has two lone pairs vs one in NH<sub>3</sub>; greater lone pair repulsion compresses the angle more in waterB Nitrogen in NH<sub>3</sub> carries a noticeably larger atomic radius than oxygen does in water in general practiceC Water's O-H bonds are generally shorter in length than NH<sub>3</sub>'s N-H bonds as frequently described in most textbook accountsD Water possesses a greater overall molecular polarity than ammonia does during normal conditions as generally observedShow answer & explanation →
Q60.
Why is F-F bond energy (159 kJ/mol) unexpectedly low compared to Cl-Cl (243 kJ/mol)?
A Lone pair-lone pair repulsion between the very close F atoms weakens the bondB Fluorine generally has a lower atomic number than chlorine in typical laboratory settingsC The F-F bond has significant ionic character unlike Cl-Cl under usual circumstancesD Chlorine atoms are larger, which directly strengthens their bond according to most researchersShow answer & explanation →
Q61.
In the valence bond (VB) theory, a covalent bond forms when:
A Atomic orbitals overlap so that electrons of opposite spin are shared between two atomsB One atom largely transfers an electron to the other atom in the majority of cases studiedC A mainly electrostatic ionic attraction develops between the atoms as widely reportedD The general electrostatic repulsion between the atoms generally decreases in standard practiceShow answer & explanation →
Q62.
Hyperconjugation involves delocalisation of electrons from:
A C-H sigma bond into an adjacent empty or pi orbitalB A lone pair delocalising directly into an adjacent sigma bondC A filled pi bond delocalising into an adjacent sigma* orbitalD Two separate lone pairs delocalising into each otherShow answer & explanation →
Q63.
The Born-Haber cycle is used to calculate:
A Lattice enthalpy of ionic compounds indirectlyB The direct bond dissociation energy of purely covalent bondsC Gibbs free energy measured directly through calorimetryD The activation energy barrier of a given reactionShow answer & explanation →
Q64.
According to VSEPR, in PCl<sub>5</sub> (trigonal bipyramidal), lone pairs prefer the equatorial position because:
A Equatorial positions have only 2 nearby 90° interactions, vs 3 for axial positionsB The axial bond positions are generally geometrically longer overall under most conditions encounteredC Equatorial bonds are inherently shorter than axial bonds in this geometry as frequently observed in practiceD PCl<sub>5</sub>'s perfect symmetry makes every position energetically identical in many documented casesShow answer & explanation →
Q65.
The resonance energy of benzene is approximately 150 kJ/mol. This means:
A Benzene is more stable than a hypothetical cyclohexatriene by 150 kJ/molB Benzene actually contains 150 kJ/mol more total energy than expectedC Drawing a single resonance structure requires an input of 150 kJD Breaking just one C-C bond in benzene requires exactly 150 kJShow answer & explanation →
Q66.
The MO electron configuration of N<sub>2</sub> is (sigma1s)2(sigma*1s)2(sigma2s)2(sigma*2s)2(pi2p)4(sigma2p)2. Its bond order is:
Show answer & explanation →
Q67.
Walsh diagrams show how molecular orbital energies change with:
A Bond angle (geometric changes)B Temperature according to conventional understandingC Bond length mainly in routine practiceD Number of electrons overallShow answer & explanation →
Q68.
In which molecule does back-bonding (pi donation from F to empty p of central atom) significantly occur?
A BF<sub>3</sub>B BCl<sub>3</sub>C BI<sub>3</sub>D BBr<sub>3</sub>Show answer & explanation →
Q69.
The dipole moment of NH<sub>3</sub> is greater than that of NF<sub>3</sub> because:
A In NF<sub>3</sub>, the N-F bond dipoles partially cancel the lone pair direction, while in NH<sub>3</sub> the bond dipoles and lone pair add togetherB NF<sub>3</sub> generally carries a greater overall molecular mass than ammonia does in every sample in most cases under typical conditionsC Ammonia forms much stronger intermolecular hydrogen bonds than NF<sub>3</sub> does in the liquid state according to standard textbooksD The individual N-F bonds in NF<sub>3</sub> are essentially non-polar despite the large electronegativity gap in general practice as frequently describedShow answer & explanation →
Q70.
Drago's rule (hard-soft concept) states that hard bases prefer:
A Hard acids (ionic, high charge density, low polarisability)B Soft acids characterised by large, easily polarisable electron cloudsC Large, highly polarisable acids regardless of charge densityD Acids that bond predominantly through covalent sharingShow answer & explanation →
Q71.
The concept of equivalent and non-equivalent resonance structures relates to:
A Whether all resonance forms have the same energy (equivalent) or different energiesB Whether the resonance forms share an identical molecular formula in most textbook accountsC Whether every resonance form obeys the octet rule largely during normal conditionsD Whether the resonance forms have equal molecular weight as generally observedShow answer & explanation →
Q72.
Isoelectronic species have the same number of electrons AND identical bond properties. Which pair is isoelectronic?
A CO and N<sub>2</sub> (both have 14 electrons and triple bonds)B CO<sub>2</sub> and NO<sub>2</sub>, despite differing electron counts and bond ordersC H<sub>2</sub>O and H<sub>2</sub>S, despite sulfur's much larger atomic radiusD NaCl and KCl, despite potassium having more electrons than sodiumShow answer & explanation →
Q73.
In a double bond, one bond is sigma and one is pi. The pi bond is WEAKER than the sigma bond because:
A Lateral p orbital overlap is less effective than head-on axial overlapB Pi bonds generally span a greater bond length than sigma bonds as frequently describedC Pi bonds contain fewer electrons than the corresponding sigma bondD Sigma bonds usually occupy inherently lower energy orbitals in most textbook accountsShow answer & explanation →
Q74.
The bond dissociation energy of Cl<sub>2</sub> > F<sub>2</sub> > Br<sub>2</sub> > I<sub>2</sub> (halogen series) because:
A Cl<sub>2</sub> has optimal overlap of 3p-3p; F-F has lone pair repulsion; Br and I have weaker, more diffuse overlapB Chlorine generally carries the highest electronegativity among all four halogens in typical laboratory settingsC Fluorine's extreme chemical reactivity is what directly sets the bond energy order under usual circumstancesD Iodine's much larger atomic size alone is what largely explains the entire trend according to most researchersShow answer & explanation →
Q75.
The van der Waals radius is larger than the covalent radius for the same atom. The ionic radius of a cation compared to the neutral atom is:
A Smaller (loss of electrons reduces shielding, pulls remaining electrons in)B Larger, since removing electrons reduces nuclear attraction overall in the majority of cases studiedC Essentially the same size as the neutral parent atom as widely reportedD Roughly double the radius of the neutral parent atom in standard practiceShow answer & explanation →