611.

The correct order of decreasing length of the bond as indicated by the arrow in the following structures is

• I > II > III

• II > I > III

• III > II > I

• I > III > II

In case of heteronuclear diatomics of the type AB, where A is more electronegative than B, bonding molecular orbital resembles the character of A more than that of B. The statement 

• is false

• is true

• cannot be evaluated since data is not sufficient

• is true only for certain systems

Dipole-induced dipole interactions are present in which of the following pairs?

• H₂O and alcohol

• Cl₂ and CCl₄

• HCl and He atoms

• SiF₄ and He atoms

Which of  the following structure is similar to graphite?

• CO

• O₂^-

• CN^-

• NO⁺

The bond angle in NF₃ (102.3°) is, smaller than NH₃ (107.2°). This is because of

• large size of F compared to H

• large size of N compared to F

• opposite polarity of N in the two molecules

• small size of H compared to N

The structure of XeF₆ is experimentally determined to be distorted octahedron. Its structure according to VSEPR theory is

• octahedron

• trigonal bipyramid

• pentagonal bipyramid

• tetragonal bipyramid

XeF₂ is isostructural with

• TeF₂

• ICl₂^-

• SbCl₃

• BaCl₂

In the following electron-dot structure calculate the formal charge from left to right nitrogen atom; $\stackrel{\mathbf{.}\mathbf{.}}{\underset{\mathbf{.}\mathbf{.}}{\mathrm{N}}}=\mathrm{N}=\stackrel{\mathbf{.}\mathbf{.}}{\underset{\mathbf{.}\mathbf{.}}{\mathrm{N}}}$ :

• -1 , -1 , +1

• -1 , +1 , -1

• +1 , -1 , -1

• +1 , -1 , +1

The sp³d² hybridisation of central atom of a molecule would lead to:

• square planar geometry

• tetrahedral geometry

• trigonal bipyramidal geometry

• octahedral geometry

Which one of the following molecules contain no $\mathrm{\pi }$-bond?

• CO₂

• H₂O

• SO₂

• NO₂