CHEMICAL BONDING

MCQ Questions

Isostructural species are those which have the same shape and hybridization. Among the given species identify the isostructural pairs.

[NF₃ and BF₃]
[BF₄- and NH₄+]
[BCl3 and BrCl₃]
[NH₃ and NO₃-]

Polarity in a molecule and hence the dipole moment depends primarily on electronegativity of the constituent atoms and shape of a molecule. Which of the following has the highest dipole moment?

CO₂
HI
H₂O
SO₂

3. The types of hybrid orbitals of nitrogen in NO2+ , NO3- and  NH4+ respectively are expected to be. 

i) sp, sp³ and sp²
ii) sp, sp² and sp³
iii) sp², sp and sp³
iv) sp², sp³ and  sp

4. Hydrogen bonds are formed in many compounds e.g. H2O, HF ,NH3. The boiling point of such compounds depends to a large extent on the strength of hydrogen bond and the number of hydrogen bonds. The correct decreasing order of the boiling points of above compounds is:

i) HF> H₂O>NH₃
ii)H₂O >HF> NH₃
iii) NH₃>HF>H₂O
iv) NH3  >H2O >HF

5. In PO₄^3- ion the formal charge on the oxygen atom of P-O bond is

i) +1
ii) -1
iii) -0.75
iv) 0.75

6. In NO₃^- ion, the number of bond pairs and the lone pairs of electrons on nitrogen atom are

i) BH₄-
ii) NH₂-
iii) CO₃^2-
iv)  H₃O+

7. Which of the following species has tetrahedral geometry?

i) BH₄-
ii) NH₂-
iii) CO₃^2-
iv) H₃O+

8. Number of π bonds and σ bonds in the  following structure is :

i) 6, 19
ii) 4 , 20
iii) 5, 19
iv) 5, 20

9. Which molecule or ion out of the following does not contain unpaired electrons?

i) N₂+
ii)O₂
iii) O₂^2-
iv) B₂

10. In which of the following molecule or ion all the bonds are not equal?

i) XeF₄
ii)BF₄-
iii) C₂H₄
iv) SiF₄