The correct order of boiling point among the following is:

1. ${\mathrm{T}}_2<{\mathrm{D}}_2<{\mathrm{H}}_2$                                 

2. n-pentane<neo pentane

3. Xe < Ar < He

4. m-nitrophenol > o-nitrophenol

The correct order of 'S$—$O' bond length is:

The linear structure is possessed by :

(1) $SnC{l}_2$

(2) $NC{O}^{-}$

(3) $N{O_2}^{+}$

(4) $C{S}_{{}^2}$

Cis-butene dioic acid $\stackrel{{\mathrm{K}}_{{\mathrm{a}}_1}\{-{\mathrm{H}}^{+}\}}{\rightleftharpoons }{{\mathrm{X}}^{-}}_1\stackrel{{\mathrm{K}}_{{\mathrm{a}}_2}\{-{\mathrm{H}}^{+}\}}{\rightleftharpoons }{\mathrm{X}}_2^{2-}$

Trans-butene dioic acid $\stackrel{{\mathrm{K}}_{{\mathrm{a}}_1}\text{'}\{-{\mathrm{H}}^{+}\}}{\rightleftharpoons }{{\mathrm{Y}}^{-}}_1\stackrel{{\mathrm{K}}_{{\mathrm{a}}_2}·\{-{\mathrm{H}}^{+}\}}{\rightleftharpoons }{\mathrm{Y}}_2^{2-}$

The incorrect statement regarding above the information is:

(1) ${\mathrm{X}}_2^{2-}$ species is more basic than ${\mathrm{Y}}_2^{2-}$ species 

(2) ${\mathrm{X}}_1^{-}$ species is more basic than ${\mathrm{Y}}_1^{-}$ species

(3) ${\mathrm{K}}_{\mathrm{a}1}$ is greater than $\mathrm{K}{\text{'}}_{\mathrm{a}2}$ 

(4) $\mathrm{K}{\text{'}}_{\mathrm{a}2}$ is greater than $\mathrm{K}{\text{'}}_{\mathrm{a}2}$

In which of the following compounds octet is complete and incomplete for all atoms:

         \(Al_2Cl_{6}\)      \(Al_{2} \left(CH_{3}\right)_{6}\)      \(AlF_{3}\)         Dimer of \(BeCl_{2}\)  Dimer of \(BeH_{2}\)

(1)      IC               IC                   IC                     C                         C

(2)      C                IC                   IC                     C                         IC

(3)      C                IC                    C                     IC                        IC

(4)      IC                C                    IC                    IC                        IC

where C denotes Complete and IC incomplete.

A compound having a metal-to-metal bond is:

1. Cupric chloride           

2. Stannous chloride

3. Mercurous chloride     

4. Mercuric chloride

Which of the following pair of elements can form an ionic compound?

The type of molecular forces of attraction present in the following compound is:

The species showing $p\pi$-$d\pi$  overlapping is :

1. $N{O_3}^{-}$

2. $P{O_4}^{3-}$

3. $C{O_3}^{2-}$

4. $N{O_2}^{-}$

Which of the following interaction lies in the range of 8 - 42 kJ/mol?

1. ${\mathrm{H}}_2...{\mathrm{H}}_2\mathrm{O}$                               

2. HCl...HCI

3. ${\mathrm{H}}_2\mathrm{O}$...HF                                 

4. all