Which out of NH3 and NF3 has higher dipole moment and why?
In NH3 and NF3, the difference in electronegativity is nearly same but the dipole moment of NH3 = (1.46D) For Example, NH3 = (0.24D)
In NH3, the dipole moments of the three N—H bonds are in the same direction as the lone pair of electron. But in NF3, the dipole moments of the three N—F bonds are in the direction opposite to that of the lone pair. Therefore, the resultant dipole moment in NH3 is more than in NF3.
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?
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
Write Lewis symbols for the following atoms and ions: S and S2– ; Al and Al3+; H and H–
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.
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.
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 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
In which of the following substances will hydrogen bond be strongest?
(a) HCl
(b) H20
(c) HI
(d) H2S
Using molecular orbital theory, compare the bond energy and magnetic character of 0+2 and O–2
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
What do you understand by bond pairs and lone pairs of electrons? Illustrate by giving one example of each type.
(a) How many a and n bonds are present in
(b) Why Hf is more stable than H2?
(c) Why is B2 molecule paramagnetic?