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 chemistry chemical bond and chemical equation coordinate bond types of bonds and properties chemical bonding and structure

"Hybridisation of central atom does not always change due to back bonding". This statement is valid for which of the following compounds ? 
(i) $CCl^- _3$                      (ii) $CCl _2$
(iii) $(SiH _3) _2 O$              (iv) $N(SiH _3) _3$

  1. (i), (ii)

  2. (i), (iii)

  3. (ii), (iii)

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

When there is back bonding from central to side atom change in hybridization takes place. Back bonding takes place when one atom has vacant orbital and one has lone pairs. 
So central atom has a lone pair and side atom must have vacant orbital 
So : $CCl^- _3$
$N (SiH _3) _3$
$Sp^3 - Sp^2$

Multiple choice chemistry chemical bond and chemical equation coordinate bond types of bonds and properties chemical bonding and structure

Which of the following molecules does not have co-ordinate bonds?

  1. $PH _{4}^{+}$
  2. $NO _2$
  3. $O _3$
  4. $CO _{3}^{2-}$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

CO3(2-) is a resonance-stabilized ion where the bonding is described by delocalized electrons. While it can be represented with coordinate bonds in Lewis structures, PH4+, NO2, and O3 clearly feature dative bonds in their standard representations.

Multiple choice chemistry chemical bonding and structure coordinate bond types of bonds and properties chemical bond and chemical equation

In potassium ferrocyanide, the nature of bond between iron and cyanide ions is :

  1. ionic bond

  2. covalent bond

  3. dative bond

  4. polar bond
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In potassium ferrocyanide, iron atom has vacant orbitals and cyanide ions have unpaired electrons. Hence, in potassium ferrocyanide, the bond between iron and cyanide ions is dative bond.

Multiple choice chemistry chemical bond and chemical equation coordinate bond types of bonds and properties chemical bonding and structure

Phosphorus forms a compound with hydrogen called phosphine, $PH _{3}$. This compound can react
with a hydrogen ion, $H^{+}$.
Which type of interaction occurs between $PH _{3}$ and $H^{+}$?

  1. Dative covalent bond

  2. Dipole- dipole forces

  3. Hydrogen bond

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

The bond formed between $P{H} _{3}$ and ${H}^{+}$ is dative covalent bond in which the bonding electrons are coming from phosphine.

Multiple choice chemistry chemical bonding and structure coordinate bond types of bonds and properties chemical bond and chemical equation

In which of the following, all four types of bonds, i.e., ionic, covalent, dative and hydrogen bonds are present?

  1. $Ice$
  2. $BeSO _{4}.4H _{2}O$
  3. $CuSO _{4}.5H _{2}O$
  4. $BaCl _{2}.2H _{2}O$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$CuSO _4\cdot 5H _2O$ exists as $[Cu(H _2O) _4]^{2+} SO _{4}^{2-}\cdot H _2O$.
It has dative bonds in $[Cu(H _2O) _4]^{2+}$, which is between water molecules and Cu. There is an ionic bond between the coordination sphere and $SO _4^{2-}$ ion. Covalent bond between S and O in  in $SO _4^{2-}$ ions and between H and O in water molecules Within the molecules of $H _2O$, there is hydrogen bonding. 

Multiple choice chemistry chemical bonding and structure coordinate bond types of bonds and properties chemical bond and chemical equation

Two elements have electronegativity of $1.2$ and $3.0$. Bond formed between them would be :

  1. ionic

  2. polar covalent

  3. co-ordinate

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

The electronegativity difference between the two atoms is $3.0 - 1.2 = 1.8$. It is large, hence, the bond formed is an ionic bond. The more electronegative atom gains one or more electrons to form an anion and the less electronegative atom loses one or more electrons to form a cation. 

Multiple choice chemistry chemical bond and chemical equation coordinate bond types of bonds and properties chemical bonding and structure

A co-ordinate bond is formed when atom in a molecule has:

  1. all its valency shell electrons shared

  2. a single unshared electron

  3. one or more unshared electron pair

  4. electric charge on it
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A co-ordinate or dative bond is a covalent bond(a shared pair of electrons) in which both the electrons come from the same atom. It is shown by an arrow and the arrow points from atom donating the lone pair to accepting atom.$\quad \quad H\ \quad \quad \quad |\ H-{ N }^{ + }\rightarrow H\ \quad \quad \quad |\ \quad \quad H$

Multiple choice chemistry chemical bonding and structure coordinate bond types of bonds and properties chemical bond and chemical equation

The type of bonds present in $CuSO 4.\, 5H _2O$ are__________.

  1. electrovalent, covalent and coordinate

  2. electrovalent and covalent

  3. electrovalent and coordinate

  4. covalent and coordinate
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A covalent bond is formed between sulfur and oxygen as they both are non metals and the bond between copper and sulfate is ionic one is metal and other non metal. Hydrated coppersulfate is a complex which is bonded to water molecules acting as ligands forming coordinate bond.