Which type of bond is formed by the head-on overlap of atomic orbitals?

A. Pi bond

B. Sigma bond

C. Delta bond

D. Phi bond

Which molecule contains resonance structures?

A. CH4

B. H2O

C. O3

D. N2

In a pi bond, the overlapping of orbitals occurs:

A. Head-on

B. Sideways

C. Diagonally

D. Perpendicular

Which of the following is NOT a property of sigma bonds?

A. Formed by head-on overlap

B. Stronger than pi bonds

C. Contains two regions of electron density

D. Allows free rotation of bonded atoms

The concept of formal charge is used to:

A. Determine the charge on an ion

B. Predict the magnetic properties of a molecule

C. Assess the distribution of electrons in a molecule

D. Measure the bond strength

a) Explain the difference between sigma (σ) and pi (π) bonds in terms of their formation and spatial orientation. [3]

b) Given a molecule with a double bond, how many sigma and pi bonds would it contain? Justify your answer. [2]

a) What is the significance of formal charge in determining the most plausible Lewis structure for a molecule? [3]

b) For the molecule CO3^2-, calculate the formal charge on the central carbon atom. [2]

a) Define resonance structures and explain their importance in understanding the structure of molecules. [3]

b) For the molecule SO3, draw two possible resonance structures. [2]

a) Describe the role of d-orbitals in the formation of pi (π) bonds. [2]

b) In a molecule with a triple bond, how many sigma (σ) and pi (π) bonds are present? [2]

c) Why are molecules with resonance structures generally more stable than those that can be represented by a single Lewis structure? [3]

a) Explain the concept of formal charge and its significance in drawing Lewis structures. [3]

b) For the molecule NO3^-, determine the formal charge on the nitrogen atom. [2]

c) How does the concept of resonance contribute to the stability of the NO3^- ion? [3]