If a dilute solution of aqueous ${\mathrm{NH}}_3$ is saturated with ${\mathrm{H}}_2\mathrm{S}$ then the product formed is

1.  $\left({\mathrm{NH}}_4\right)2\mathrm{S}$

2.  ${\mathrm{NH}}_4\mathrm{HS}$

3.  ${\left({\mathrm{NH}}_4\right)}_2{\mathrm{S}}_{\mathrm{x}}$

4.  ${\mathrm{NH}}_4\mathrm{OH} + \mathrm{S}$

The reaction that does not produce nitrogen is

1.  Heating ${\left({\mathrm{NH}}_4\right)}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$

2. Excess of ${\mathrm{NH}}_3 + {\mathrm{Cl}}_2$

3. Heating of ${\mathrm{NaN}}_3$

4. Heating of ${\mathrm{NH}}_4{\mathrm{NO}}_3$

With respect to halogens, four statements are given below

(I) The bond dissociation energies for halogens are in the order: ${\mathrm{l}}_2 < {\mathrm{F}}_2 < {\mathrm{Br}}_2 < {\mathrm{Cl}}_2$

(II) The only oxidation state is —1

(III) The amount of energy required for the excitation of electrons to the first excited state decreases progressively as we move from F to l

(IV) They form ${\mathrm{HX}}_2^{-}$ species in their aqueous solutions (X = halogen)

The correct statements are

1.  I, II, IV

2.  I, III, IV

3.  II, III, IV

4.  I, III

Bleaching powder contains a salt of an oxoacid as one of its components. The anhydride of that acid is

1.  ${\mathrm{Cl}}_2\mathrm{O}$

2.  ${\mathrm{Cl}}_2{\mathrm{O}}_7$

3.  ${\mathrm{ClO}}_2$

4.  ${\mathrm{Cl}}_2{\mathrm{O}}_6$

Which of the following molecular structures is not possible?

1.  ${\mathrm{OF}}_2$

2.  ${\mathrm{SF}}_2$

3.  ${\mathrm{OF}}_4$

4.  ${\mathrm{SF}}_4$

Which of the following salt/s of ${\mathrm{H}}_3{\mathrm{PO}}_3$ exists?

I. ${\mathrm{NaH}}_2{\mathrm{PO}}_3$    II. ${\mathrm{Na}}_2{\mathrm{HPO}}_3$    III. ${\mathrm{Na}}_3{\mathrm{PO}}_3$  

1.  I and II only

2.  I, II, and III

3.  II and III only

4.  III only

The gas which liberates bromine from a solution of KBr is

1.  ${\mathrm{Cl}}_2$

2.  ${\mathrm{l}}_2$

3.  ${\mathrm{SO}}_2$

4.  Hl

Which one of the following is not a valid structure for dinitrogen oxide?

l.  

ll. 

lll. 

lV. 

1.  l

2.  ll

3.  lll

4.  lV

The molecule which is NOT hydrolyzed by water at 25$°$C is

1.  ${\mathrm{AlCl}}_3$

2.  ${\mathrm{SiCl}}_4$

3.  ${\mathrm{BF}}_3$

4.  ${\mathrm{SF}}_6$

The number of P-H bond(s) in ${\mathrm{H}}_3{\mathrm{PO}}_2$, ${\mathrm{H}}_3{\mathrm{PO}}_3$, and ${\mathrm{H}}_3{\mathrm{PO}}_4$, respectively, is

1.  2, 0, 1

2.  1, 1, 1

3.  2, 0, 0

4.  2, 1, 0