Chemical Bonding | Assignment 1
Molecular Orbital Theory
Q1. The highest occupied molecular orbital in N2 and O2+ respectively are (take x as internuclear axis)
(b) π2py, π2pz
(c) σ*2px, σ2px
(d) π*2py, π*2pz
Q2. The number of anti bonding electrons in NO and CO according to MO theory are respectively
(b) 2, 2
(c) 3, 2
(d) 2, 3
Q3. The molecule in which the bond order increases upon addition of an electron is
(b) B2
(c) P2
(d) N2
Q4. The correct statement among the following is
(a) N2 has higher bond order than N2+ and hence has larger bond length compared to N2+
(b) N2+ has higher bond order than N2 and hence has larger bond length compared to N2
(c) N2 has higher bond order than N2+ and hence has larger dissociation energy compared to N2+
(d) N2 has lower bond order than N2+ and hence has larger dissociation energy compared to N2+
Q5. Correct combination of π and π* orbitals in B2 molecule is
(b) Ungerade Gerade
(c) Gerade Gerade
(d) Ungerade Ungerade
Q6. Boron in BCl3 has
(b) sp2 hybridization
(c) sp3 hybridization
(d) no hybridization
Q7. According to Bent's rule, for p-block elements the correct combination of geometry around the central atom and the position of more electronegative substituent is
(b) trigonal bipyramidal and equatorial
(c) square pyramidal and axial
(d) square pyramidal and equatorial
Q8. Removal of an electron from NO molecule results in
(B) an EPR active species
(C) electrons in HOMO being closer to oxygen than to nitrogen 2p orbitals
(D) electrons in HOMO being closer to nitrogen than to oxygen 2p orbitals
The correct answer is
(a) A only
(b) A and C
(c) B and D
(d) A, B and C
Column I | Column II |
---|---|
(A) Non donor | (I) 520 |
(B) Weak donor | (II) 500 |
(C) Strong donor | (III) 450 |
(D) π donor | (IV) 360 |
(a) A-I, B-II, C-III, D-IV
(b) A-III, B-IV, C-II, D-I
(c) A-I, B-III, C-IV, D-II
(d) A-IV, B-III, C-II, D-I
Q10. Among the following diatomic molecules, the shortest bond length is to be found in
(b) N2
(c) O2
(d) F2
Q11. The paramagnetic species among the following is
(b) C2
(c) O22-
(d) CO
(b) antibonding
(c) ionic
(d) non bonding
Ans Key
1.a 2.a 3.b 4.c 5.b 6.b 7.a 8.b 9.c 10.b 11.a 12.d