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

The complete hydrolysis of \(\mathrm{XeF}_6\)${}_{}$ results in the formation of:
 

Phosphorous reacts with chlorine gas to give a colorless liquid. which fumes in moist air to produce HCl and

1.  ${\mathrm{POCl}}_3$

2.  ${\mathrm{H}}_3{\mathrm{PO}}_3$

3.  ${\mathrm{PH}}_3$

4.  ${\mathrm{H}}_3{\mathrm{PO}}_4$

Ammonia is NOT produced in the reaction of

1.  ${\mathrm{NH}}_4\mathrm{Cl}$ with KOH

2.  AIN with water

3.  ${\mathrm{NH}}_4\mathrm{Cl}$ with ${\mathrm{NaNO}}_2$

4.  ${\mathrm{NH}}_4\mathrm{Cl}$ with $\mathrm{Ca}{\left(\mathrm{OH}\right)}_2$

NO₂ is the anhydride of

1. HNO₃

2. HNO₂

3. HNO₃ + HNO₂

4. None of the above

Which is not hydrolysed with water?

1. ${\mathrm{PCl}}_3$

2. ${\mathrm{NF}}_3$

3. ${\mathrm{NCl}}_3$

4. ${\mathrm{BCl}}_3$