Chemical Bonding

Question 1

Bond order, bond strength, bond dissociation energy, bond length relation

Answer 1

B.O ∝ B.S ∝ B.DE ∝ 1/B.L

Question 2

Number electrons v/s bond order

Answer 2

No: of electrons B.O
10 1
11 1.5
12 2
13 2.5
14 3
15 2.5
16 2
17 1.5
18 1

Question 3

What is bond order

Answer 3

Number of chemical bonds b/w two atoms

Question 4

Calculating bond order

Answer 4

B.O = (no: of bonding electron - no: of antibonding electron) / 2

• If B.O is +ve: molecule is stable
• B.O is zero: molecule doesn’t exist
• B.O is 1: single bond b/w atoms
• B.O is 2: double bond b/w atoms
• B.O is 3: triple bond b/w atoms

Question 5

No: of hybrid orbitals

Answer 5

½(V + M - C + A)

V: valence electrons
M: monovalent atom
C: charge on cation
A: charge on anion

Question 6

Formal charge

Answer 6

F.C = V - L - ½S

V: valence electrons
L: lone pair
S: shared pair of electrons

Question 7

Bond order of isoelectronic species

Answer 7

They have same B.O as they have same number of electrons

Question 8

Steric number

Answer 8

No: of σ bonds + no: of lone pair

Question 9

Predicting hybridisation and geometry

Answer 9

Steric no: Hyb Geometry
2 sp linear
3 sp² trigonal planar
4 sp³ tetrahedral
5 sp³d trigonal bp
6 sp³d² octahedral
7 sp³d³ pentagonal bp

*bp = bi pyramidal