What is meant by the term bond order? Calculate the bond order of N2, O2, O2+,O2–
Bond order is defined as the half of the difference between the number of electrons present in bonding and antibonding molecular orbitals.
Match the shape of molecules in Column I with the type of hybridization in Column II.
Column I | Column II |
(i) Tetrahedral | (a) sp2 |
(ii) Trigonal | (b) sp |
(iii) Linear | (c) sp3 |
Match the species in Column I with the geometry/shape in Column II.
Column I | Column II |
(i) H30+ | (a) Linear |
(ii) HC = CH | (b) Angular |
(iii) Cl0–2 | (c) Tetrahedral |
(iv) NH+4 | (d) Trigonal bipyramidal |
– | (e) Pyramidal |
Describe the change in hybridisation (if any) of the Al atom in the following reaction. AlCl3 + Cl– ——>AlCl4- .
Which hybrid orbitals are used by carbon atoms in the following molecules?
(a) CH3-CH3 (b) CH3-CH = CH2 (c) CH3-CH2-OH (d) CH3-CHO (e) CH3COOH.
Out of bonding and antibonding molecular orbitals, which one has lower energy and which one has higher stability?
Write Lewis symbols for the following atoms and ions: S and S2– ; Al and Al3+; H and H–
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?
(a) C02
(b) HI
(c) H20
(d) S02
In N0–3 ion, the number of bond pairs and lone pairs of electrons on nitrogen atom are
(a) 2, 2 (b) 3, 1 (c) 1,3 (d) 4, 0
In which of the following substances will hydrogen bond be strongest?
(a) HCl
(b) H20
(c) HI
(d) H2S
3PO3 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 H3PO3? If not, give reasons for the same.
The skeletal structure of CH3COOH as shown below is correct, but some of the bonds are shown incorrectly. Write the correct Lewis structure for acetic acid.
Considering X-axis as the intemuclear axis which out of the following will not form a sigma bond and why? (a) Is and Is (b) Is and 2px (c) 2py and 2py (d) Is and 2s
Write the important conditions required for the linear combination of atomic orbitals to form molecular orbitals.
Name the two conditions which must be satisfied for hydrogen bonding to take place in a molecule.
Define Lattice energy. How is Lattice energy influenced by (i) Charge on the ions (ii) Size of the ions?
Explain the diamagnetic behaviour of P2 molecule on the basis of molecular orbital theory.
(a) Define dipole moment. What are the units of dipole moment?
(b) Dipole moment values help in predicting the shapes of covalent molecules. Explain.
In PO43- ion the formal charge on the oxygen atom of P – O bond is
(a) +1 (b) -1 (c) -0.75 (d) +0.75
Which molecule/ion out of the following does not contain unpaired electrons?
(a) N+2
(b) 02
(c) O22-
(d) B2
Which of the following statements are correct about CO32- ?
(a) The hybridization of central atom is sp3.
(b) Its resonance structure has one C – O single bond and two C = O double bonds.
(c) The average formal charge on each oxygen atom is 0.67 units.
(d) All C – O bond lengths are equal.
Using molecular orbital theory, compare the bond energy and magnetic character of 0+2 and O–2
Is there any change in the hybridisation ofB and N atoms as a result of the following reaction ? BF3 + NH3 ——-> F3 B.NH3
What do you understand by bond pairs and lone pairs of electrons? Illustrate by giving one example of each type.