Chemistry

Chemical Bonding and Molecular Structure

1,277 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 ionic bond atomic structure and chemical bonding chemistry


An electrovalent bond is formed when a metal atom transfers one or more electrons to a non-metal atom in :

  1. ionic compounds

  2. covalent compounds

  3. metallic compounds

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

An electrovalent bond is formed when a metal atom transfers one or more electrons to a non-metal atom and these compounds are called ionic compounds.

Multiple choice ionic bond atomic structure and chemical bonding chemistry

Which of the following factor(s) favour the formation of ionic bond?

  1. The electrostatic attraction between charged ions in the crystal (i.e, lattice energy) should be low.

  2. Both atoms should be equal in size.

  3. The combining elements should differ by at least 2.0 in electronegativity.

  4. The cation and anion should have inert gas electronic configuration.
Reveal answer Fill a bubble to check yourself
C,D Correct answer
Explanation

The following factors favour the formation of ionic bond.
The electrostatic attraction between charged ions in the crystal (i.e, lattice energy) should be high.
One of the atoms (metal) should be large in size. Other atom (non metal) should be small in size.
The combining elements should differ by at least 2.0 in electronegativity.
The cation and anion should have inert gas electronic configuration.

Multiple choice ionic bond atomic structure and chemical bonding chemistry

The charged particles that attract each other to form electrovalent compounds are _________.

  1. Protons and neutrons

  2. Cation and anion

  3. Electrons

  4. none of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cation$\rightarrow $positively charged

Anion$\rightarrow $negatively charged
           Negative charges attract each other
Cation and onion are the charged particles that attract each other to form electrovalent compounds.

Multiple choice chemistry pure substances and mixtures: separation of mixtures difference between mixtures and compounds pure substance and mixtures types of pure substances

In which of the following compounds resonance does not occur
(i) ${H _2}O$
(ii) $Si{O _2}$
(iii) $S{O _3}$
(iv) $C{O _2}$

  1. Both (i) and (iv)

  2. Both (i) and (ii)

  3. Both(iii) and (iv)

  4. (i),(ii)and(iv)
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Resonance involves delocalization of pi electrons through conjugated systems or empty d-orbitals where applicable. H2O has only single bonds and lone pairs, so no resonance occurs. SiO2 exists as a giant covalent network of silicon-oxygen single bonds without resonance structures. Thus, both (i) and (ii) do not exhibit resonance.

Multiple choice chemistry pure substances and mixtures: separation of mixtures difference between mixtures and compounds pure substance and mixtures types of pure substances

Ionic compounds have ____ melting and boiling points whereas covalent compounds have _____ melting and boiling point.

  1. low, high

  2. moderate, low

  3. high, low

  4. moderate, high
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ionic compounds consist of strong electrostatic forces between ions, requiring high energy to break, resulting in high melting and boiling points. Covalent compounds consist of molecules held by weaker intermolecular forces, resulting in lower melting and boiling points.

Multiple choice chemistry atoms, molecules and radicals molecular formula and valency valency and chemical formulae combining capacity and chemical formulae

Electrovalencies of three metals $A, B, C $are $1, 2, 3$ respectively and those of non-metals $X, Y, Z$ and $3, 2, 1$ respectively. Which among the following couldn't be the formula of the various ionic compounds formed between the respective metals and non-metals?

  1. $A _3 X, BY, CZ _3$
  2. $AZ, B _3 X _2, C _2 Y _3$
  3. $AZ _3, B _2X, C _3Y _2$
  4. $A _2Y, BZ _2, CX$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The incorrect formula's are; $AZ _{3}$, $B _{2}X$, $C _{3}Y _{2}$

Multiple choice physics electric charges and fields potential energy of a dipole in external field potential due to electric dipole electric dipole

Carbon tetrachloride has zero dipole moment because of ________.

  1. planar structure

  2. Smaller size of C and Cl atoms

  3. regular tetrahedral structure

  4. none of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Carbon tetrachloride molecule has zero dipole moment even though C and Cl have different electronegativities and each of the C - Cl bond is polar and has some dipole moment. This is because the individual dipole moments cancel out because of the symmetrical tetrahedral shape of the molecule.



Multiple choice chemistry substances in common use salts and their properties study of some important salts salts used in daily life

Statement 1: One mole of NaCl contains $2$ moles of ions.
Statement 2: NaCl is a stable salt at room temperature.

  1. <p>Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation of Statement 1.</p>

  2. <p>Both Statement 1 and Statement 2 are correct and Statement 2 is not the correct explanation of Statement 1.</p>

  3. <p>Statement 1 is correct but Statement 2 is not correct.</p>

  4. <p>Statement 1 is not correct but Statement 2 is correct.</p>

  5. <p>Both the Statement 1 and Statement 2 are not correct</p>
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Option (B) is correct.

Statement 1:  One mole of $NaCl$ contains 2 moles of ions i.e. a mole of chloride and a mole of sodium.Every $NaCl$ molecules has a $Na$ and a $Cl^-$ atom. So, if you have $6.022x10^{23}$ molecules, you will have that same number of $Na$ atoms and $Cl^-$ atoms, and by definition, 1 mole is $6.022x10^{23} $atoms.

Statement 2: $NaCl$ is a stable salt at room temperature.Sodium and chlorine forms a strong ionic bond, completing the octet of both atoms.They are arranged in a face centered cubic crystal structure where each $Na^+$ or $Cl^-$ ion is surrounded by 6 of the opposite ions forming an octahedron. This makes sodium chloride a stable compound.

Multiple choice chemistry substances in common use salts and their properties study of some important salts salts used in daily life

Statement 1: Crystals of sodium chloride go into aqueous solution as ions.
Statement 2: The sodium ion has a $1+$ change and the chloride ion has a $1-$ charge and they are hydrated by the water molecules.

  1. <p>Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation of Statement 1.</p>

  2. <p>Both Statement 1 and Statement 2 are correct and Statement 2 is not the correct explanation of Statement 1.</p>

  3. <p>Statement 1 is correct but Statement 2 is not correct.</p>

  4. <p>Statement 1 is not correct but Statement 2 is correct.</p>

  5. <p>Both the Statement 1 and Statement 2 are not correct. </p>
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Statement 1: Crystals of sodium chloride go into aqueous solution as ions.
$\displaystyle NaCl \rightleftharpoons Na^+ (aq) + Cl^- (aq) $
Statement 2: The sodium ion has a $1+$ change and the chloride ion has a $1−$ charge and they are hydrated by the water molecules.
Each sodium ion ( or each chloride ion) is surrounded by several water molecules.
Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation of Statement 1.