Chemistry Class 11 NCERT Solutions: Chapter 4 Chemical Bonding and Molecular Structure Part 3
Q: 12. can be represented by structures 1 and 2 shown below. Can these two structures be taken as the canonical forms of the resonance hybrid representing If not, give reasons for the same.
Answer: The given structures cannot be taken as the canonical forms of the resonance hybrid of because the positions of the atoms have changed.
Q: 13. Write the resonance structures for.
The resonance structures are:
Q: 14. Use Lewis symbols to show electron transfer between the following atoms to from cations and anions:
(A) K and S
(B) Ca and O
(C) Al and N
(A) K and S:
The electronic configurations of K and S are as follows:
K: 2, 8, 8, 1
S: 2, 8, 6
Sulphur (S) requires 2 more electrons to complete its octet. Potassium (K) requires one electron more than the nearest noble gas i.e., Argon. Hence, the electron transfer can be shown as:
The electronic configurations of Ca and O are as follows:
Oxygen requires two electrons more to complete its octet, whereas calcium has two electrons more than the nearest noble gas i.e., Argon. Hence, the electron transfer takes place as:
(C) Al and N:
The electronic configurations of Al and N are as follows:
Nitrogen is three electrons short of the nearest noble gas (Neon), whereas aluminium has three electrons more than Neon. Hence, the electron transference can be shown as:
Q: 15. Although both and are triatomic molecules, the shape of molecule is bent while that of is linear. Explain this on the basis of dipole moment.
According to experimental results, the dipole moment of carbon dioxide is zero. This is possible only if the molecule is linear so that the dipole moments of C-O bonds are equal and opposite to nullify each other.
on the other hand, has a dipole moment value of D (though it is a triatomic molecule as ).
The value of the dipole moment suggests that the structure of molecule is bent where the dipole moment of O-H bonds are unequal.