Which of the following are isoelectronic and isostructural ?

(1) $N{O_2}^{+}, C{O}_2$                                    

(2) $N{O_3}^{-},B{F}_3$

(3) $N{H}_3,C{H_3}^{-}$                                      

(4) All of these

The correct order of acidic strength is :

1. ${\mathrm{Cl}}_2{\mathrm{O}}_7>{\mathrm{SO}}_2>{\mathrm{P}}_4{\mathrm{O}}_{10}$                   

2. ${\mathrm{CO}}_2>{\mathrm{N}}_2{\mathrm{O}}_5>{\mathrm{SO}}_3$

3. ${\mathrm{Na}}_2\mathrm{O}>\mathrm{MgO}>{\mathrm{Al}}_2{\mathrm{O}}_3$                   

4. ${\mathrm{K}}_2\mathrm{O}>\mathrm{CaO}>\mathrm{MgO}$

In which of the following molecules / ions are all the bond angles not equal?

(1) $Si{F}_4$                                                   

(2) $IC{l_4}^{-}$ 

(3) $S{F}_4$                                                    

(4) $PC{l_4}^{+}$

No S-S bonds are present in?

1. \(S_{2}O_{3}^{2-}\)                                           

2. \(S_{2}O_{4}^{2-}\)

3. \(S_{2}O_{5}^{2-}\)                                                

4. \(S_{2}O_{7}^{2-}\)

What is the correct order from the weakest to the strongest carbon-oxygen bond for the following species? 

$CO, C{O}_2, C{O_3}^{2-}, C{H}_{3}OH$

(1) $C{H}_{3}OH <C{O_3}^{2-}<C{O}_2<CO$                         

(2) $CO<C{O}_2 <C{O_3}^{2-}<C{H}_{3}OH$

(3) $C{H}_{3}OH <C{O_3}^{2-}<CO<C{O}_2$                         

(4) $C{H}_{3}OH <C{O}_2<C{O_3}^{2-}<CO$

According to Molecular orbital theory which of the following statement is incorrect?

(1) LUMO level for $C_2$molecule is ${\sigma }_{2px}$ orbital.      

(2) In $C_2$ molecules both the bonds $\mathrm{\pi }$ are bonds.

(3) $C_2$ is paramagnetic but ${C_2}^{2-}$is diamagnetic.     

(4) In ${C_2}^{2-}$ ion there is one $\sigma$ and two $\pi$ bonds.

Match the ionization processes listed in column – I with the changes observed as listed in
column-II. For this use the codes given below:

       Column- I                                                                 Column - II

(a) $N_2 \to N_2^{+}$                                 (p) Bond order increases and magnetic property is changed.

(b) ${O_2}^{+}\to {O_2}^{2+}$                               (q) Bond order decreases and magnetic property is not changed.

(c) $B_2\to {B_2}^{+}$                                   (r) Bond order increases and magnetic property is not changed.

(d) $N{O}^{-}\to NO$                                  (s) Bond order decreases and magnetic property is changed.

Note : Here change in magnetic property refers to change from diamagnetic to paramagnetic
or paramagnetic to diamagnetic. 

                          a      b          c        d
1.                       s       q          p        r
2.                       s       p          q        r
3.                       r       q          s        p
4.                       p       s         q        r

Arrange the following molecules from most to least polar.

$C{H}_4 C{F}_{2}C{l}_2 C{F}_2{H}_2 CC{l}_4 CC{l}_2{H}_2$
$I II III IV V$

(1) III>V>II > IV=I                                 

(2) II>IV>III>IV>I

(3) III>II>V>IV>I                                 

(4) V>III>II>IV=I    

Which of the following statements is correct?

1. ${\left(C{H}_3\right)}_3$ COH is less acidic than ${\left(C{H}_3\right)}_3$ SiOH.

2. Like CO, its analogue of Si is not stable.

3. In phosgene, C-O bond length is longer than expected while C-Cl bond length is shorter.

4. All of these

The boiling point of $CC{l}_4$ is higher than that of $CHC{l}_3$ because :

(1) The dipole moment of $CC{l}_4$ is greater than that of $CHC{l}_3$

(2) $CC{l}_4$ forms hydrogen bonds.

(3) $CC{l}_4$ has higher molecular mass than that of $CHC{l}_3$

(4) $CC{l}_4$ is more ionic than $CHC{l}_3$