The electronegativity difference between N and F is greater than that between N and H yet the dipole moment of NH₃ (1.5 D) is larger than that of NF₃ (0.2 D). This is because:

(1) in NH₃ as well as in NF₃ the atomic dipole and bond dipole are in the same direction
(2) in NH₃ the atomic dipole and bond dipole are in the same direction whereas in NF₃ these are in opposite directions
(3) in NH₃ as well as NF₃ the atomic dipole and bond dipole are in opposite directions
(4) in NH₃ the atomic dipole and bond dipole are in the opposite directions whereas in NF₃ these are in the same directions

The correct order of electronegativity of hybrid orbitals of carbon is:

(1) sp>sp²<sp³             

(2) sp>sp²>sp³

(3) sp<sp²>sp³             

(4) sp<sp²<sp³

Which of the following species has a linear shape?

(1) ${\mathrm{NO}}_2^{-}$

(2) SO₂

(3) ${\mathrm{NO}}_2^{+}$

(4) O₃

Which of the following is the most basic oxide?
(1) Al₂O₃

(2) Sb₂O₃

(3) Bi₂O₃

(4) SeO₂

Which of the following is not a correct statement?

(1) The electron-deficient molecules can act as Lewis acids

(2) The canonical structures have no real existence

(3) Every AB₅ molecule does, in fact, have square pyramid structure

(4) Multiple bonds are always shorter than corresponding single bonds

The number of unpaired electrons in a paramagnetic diatomic molecule of an element with atomic mass 16 is :

1. 2

2. 3

3. 4

4. 1

Which of the following is not isostructural with SiCl₄?

(a) SCl₄            (b) ${\mathrm{SO}}_4^{2-}$               (c) ${\mathrm{PO}}_4^{3-}$                 (d) ${\mathrm{NH}}_4^{+}$

Least stable hydride is:

(1) stannane 

(2) silane 

(3)  plumbane 

(4) germane

Correct order of strength of H-bond in the following compounds is : 

(1) $H_{2}O > H_2{O}_2 > HF > H_{2}S$ 

(2) $HF \ge H_2{O}_2 > H_{2}O > H_{2}S$

(3) $HF >\hspace{0.17em}{H}_{2}O > H_{2}S > H_2{O}_2$

(4) $HF >\hspace{0.17em}{H}_2{O}_2 > H_{2}O > H_{2}S$

Molecule having non-polar as well as polar bonds but the molecule as a whole is polar:

(a) $S_2{F}_2$

(b) ${\mathrm{N}}_2{\mathrm{O}}_4$

(c) ${\mathrm{Si}}_2{\mathrm{H}}_6$                                           

(d) ${\mathrm{I}}_2{\mathrm{Cl}}_6$