Chemical bonding and shape of molecules

Very Short Question: (2 marks each)

1. Predict the structure of methane based on hybridization.

2. Identify the hybridization of the indicated atom in each of the following molecules:

   • Be in BeF2
   • B in BF3
   • N in NH3

3. Draw the shapes of sp & sp2hybrid orbitals.

4. How do you predict the molecular geometry of NH3 based on VSEPR model?

5. Draw the structures of ethyne indicating the structures of σ-bonds &π-bonds.

6. Draw the molecular orbital picture of ethane.

7. How would interpret that the all four C-H bonds of methane are identical?

8. The bond angle at the central atom in NF3103°, whereas in BF3 is 120°. What factor accounts for the difference in the bond angle?

9. Define hybridization. Draw the orbital picture of a hydrocarbon showing the tetrahedral structure.

10. Predict the mode of hybridization in:

    • C of C2H4
    • B of BF3

11. What is the mode of hybridization of the central atom whose molecular geometry is tetrahedral? And, give an example of its.

12. Mention one example of each:

    • Tetrahedral Hybridization.
    • Triongal hybridization.

13. Write any two important characteristics of tetrahedral hybridization.

Short Question: (5 marks each)

1. What do you mean by sp2 hybridization? Using any example explain the molecular geometry involved.

2. Explain the state of hybridization in ethyne molecule.

3. Using VSEPR theory, explain the shapes of BeF2& BF3.

4. How would you predict the molecular geometry of NH3 based on VSEPR model?

5. Why is H-O-H bond angle on water molecule comparatively higher than H-S-H bond angle in H2S molecule?

Long Question: (10 marks each)

1. Write notes on VSEPR model.