Bonding

Question 1

What is chemical bond?

Answer 1

The attractive forces which hold the various constituents (atom, ion) together in different chemical reactions are chemical bonds.

Question 2

What are the differences between inert and noble gases?

Answer 2

Key Differences:
Scope: All noble gases are inert, but not all inert gases are noble gases. For example, nitrogen can be considered an inert gas in some situations, but it is not a noble gas.
Reactivity: Noble gases are inherently nonreactive due to their full electron shells. Inert gases are nonreactive due to specific conditions but might react under different circumstances.

Question 3

What type of bond is HCl ?

Answer 3

Polar Covalent Bond

Question 4

Arrange the bonds in terms of their bond strength.

Answer 4

Ionic > Covalent > Coordinate Covalent> Metallic > Hydrogen Bond > Vander waal

Question 5

What is Ionic Bond?

Answer 5

An ionic bond is a type of chemical bond that forms between metal and non metal when metal donates one or more electrons to another non metal. This transfer of electrons causes the donating atom to become a positively charged ion (cation) and the receiving atom to become a negatively charged ion (anion). The strong electrostatic attraction between the oppositely charged ions holds them together, creating an ionic compound. This type of bonding typically occurs between metals and nonmetals, such as in sodium chloride (NaCl).

Question 6

What is electrovalency?

Answer 6

The number of valence electrons involved in formation of ionic bond is electrovalency.

Question 7

Conditions for formation of ionic bond are?

Answer 7

• One atom should have low I.P (Metal)
• Other must have high E.A (Non metal)
• Lattice energy should be high

Question 8

What are the characters of Ionic Bond?

Answer 8

• Direction : Non directional
• Density : High
• M.P and B.P : High (Due to high electrostatic force of attraction)
• State is Solid
• Solubility : Soluble in polar solvents like water
• Electrical conductivity : Yes
• Reaction speed : Fast

Question 9

Atoms are more stable in bonded form than in uncombined state due to?

Answer 9

Decrease in potential energy in combined form increasing the overall stability in the bond formation process

Question 10

The cations and anions are held by a force of attraction called?

Answer 10

electrostatic force of attraction

Question 11

Metal + Non-Metal = ?

Answer 11

Ionic bond

Question 12

Non-Metal + Non-Metal = ?

Answer 12

Covalent bond

Question 13

Generally , Ionic bonds are formed between atoms of electronegativity difference greater than?

Answer 13

1.8 ( in Pauling scale)

Question 14

Why are compounds called ionic even though they have covalent bond as well?

Answer 14

As the particles of the compound are ions

Question 15

Solubility of Ionic and Covalent compounds?

Answer 15

Ionic - soluble in polar solvents (water)
Covalent - soluble in nonpolar solvents (benzene, diethyl ether)

Question 16

What is covalent Bond and what type of compound is HCl?

Answer 16

The bond formed by mutual sharing of electrons between non-metals is known as covalent bond.

Polar Covalent Bond

Question 17

What is coordinate covalent bond?

Answer 17

The bond formed by the sharing of electrons between two combining atoms , in which both the shared electrons contributed by one of the bonded atoms only, it is coordinate covalent bond.

Question 18

What is Lewis acid and Lewis base?

Answer 18

Lewis acid - electron pair acceptor that accept electrons from lewis base
Lewis base - electron pair donor having completely filled shell

Question 19

Failure of octet rule is due to?

Answer 19

1. Compounds of Hydrogen
2. Molecules having incomplete octet are also stable. BeCl2, BF3
3. Molecules having super-octet structures i.e. having more than 8 electrons
   4.Compounds of transition metals

Question 20

What is resonance?

Answer 20

The occurrence of multiple structures of a compound is called resonance.

Question 21

What is resonance hybrid?

Answer 21

The real structure of the molecule or ion is hybrid of these structures which is called resonance hybrid.

Question 22

Why does AlF3 form ionic bond and AlCl3 form covalent bond?

Answer 22

AlF₃ is ionic because the high electronegativity of fluorine and the small, hard-to-polarize F⁻ ion lead to a large transfer of electrons and the formation of strong ionic bonds.
AlCl₃ is covalent because the electronegativity difference is smaller, and the more easily polarizable Cl⁻ ion allows for electron sharing, leading to covalent bonding.

Chlorine - Easily polarizable
Florine - Not easily polarizable

Question 23

Covalent bond is formed by?

Answer 23

-Sharing of electrons between combining atoms.
- Overlapping of atomic orbitals

Question 24

Properties of covalent bond:

Answer 24

1. Directional
2. Low melting and Boiling points
3. No electrical conductivity
4. Soluble in non polar solvents like alcohol.

Question 25

Conditions for formation of covalent bond:

Answer 25

1. High Ionizational Potential 2. High Electron Affinity 3. Low electronegativity difference

Question 26

What is coordinate covalent bond?

Answer 26

The bond formed between two species where the electrons for sharing are contributed by only one bonded specie is known as coordinate covalent bond.

Question 27

Why is coordinate covalent bond called semi polar bond?

Answer 27

A semipolar bond has characteristics that are intermediate between purely covalent and ionic bonds. In an ionic bond, electrons are completely transferred. In a covalent bond, electrons are equally shared. In a coordinate covalent (semi polar) bond, one atom provides both electrons, leading to a bond that has some directionality and polarity but still involves electron sharing so, it is called semipolar bond.

Question 28

Conditions for formation of coordinate covalent bond :

Answer 28

1. The donor atom must posses at least one lone pair of electron 2. The acceptor atom must only need one pair of electrons to acquire closest noble gas configuration.

Question 29

Why was concept of resonance introduced?

Answer 29

the concept of resonance is fundamental in chemistry for explaining the stability, structure, and reactivity of molecules, especially when a single structural representation cannot accurately describe the molecule's electron distribution. It helps chemists better understand how certain molecules behave and predict their properties more accurately. In molecules like ozone (O₃), resonance explains why bond lengths are intermediate between single and double bonds. Without resonance, we might expect different bond lengths, but the true structure shows equal bond lengths due to electron delocalization.

Question 30

What is hydrogen bond?

Answer 30

The force of attraction between already bonded hydrogen with highly electronegative elements like FON is hydrogen bond.

Question 31

Why does Nitrogen create hydrogen bond but not Cl?

Answer 31

Due to small size of N

Question 32

Strength of hydrogen bond increases with increase in ?

Answer 32

Electronegativity of FON. F>O>N

Question 33

o-nitrophenol and p-nitrophenol

Answer 33

O- intramolecular P- intermolecular

Question 34

van der Waal's Force :

Answer 34

1. Instantaneous force of attraction 2. Weaker than hydrogen bond 3. Increases with increase in size, surface area and polarity.

Question 35

Dipole-Dipole Interaction

Answer 35

Kessom Force

Question 36

Ion-Dipole Interaction

Answer 36

London Force

Question 37

Instantaneous dipole - induced dipole interaction :

Answer 37

London Force ( Non-polar )