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Multiple choice chemistry p- block elements-ii compounds of phosphorus - pcl3 phosphorus halides compounds of phosphorus compounds of phosphorus- pcl5

What kind of a molecule is ${P}{Cl} _{3}$?

  1. Ionic

  2. Polar covalent

  3. Non polar covalent

  4. none of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$PCl _3$ is a polar covalent molecule. It is polar because chlorine atoms are more electronegative than phosphorus atom and hence the polartity of the molecule is towards Chlorine atoms.
It is covalent because, Phosphorus has ive electrons in its outermost shell. It requires three more to complete its octet. Each chlorine atom has seven electrons in their outermost shell, they all require one electron each to complete their octet. Thus both phosphorus and chlorine complete their octet by mutually sharing their electrons. Hence this molecule is polar covalent in nature.

Multiple choice chemistry p- block elements-ii compounds of phosphorus - pcl3 phosphorus halides compounds of phosphorus compounds of phosphorus- pcl5

What is produced as an impurity during the production of ${PCl} _{3}$:

  1. ${PCl} _{5}$
  2. ${POCl} _{3}$
  3. ${PSCl} _{3}$
  4. ${Cl} _{2}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During the indusrial preparation of ${PCl} _{3}$, ${PCl} _{5}$ or Phosphorus Pentachloride is produced as an impurity. The balanced equation can be written as-
${PCl} _{3}$ ${+}$ ${Cl} _{2}$ ${=}$ ${PCl} _{5}$
Thus this impurity formation can be stopped by continual removal of ${PCl} _{3}$ as it is formed.

Multiple choice chemistry p- block elements-ii compounds of phosphorus - pcl3 phosphorus halides compounds of phosphorus compounds of phosphorus- pcl5

Aqueous solution of PBr$ _{3}$ conducts electricity due to the presence of:

  1. $\mathrm{HOBr}$
  2. $\mathrm{HBr}$
  3. $\mathrm{H} _{3}\mathrm{P}\mathrm{O} _{4}$
  4. $\mathrm{H} _{2}\mathrm{O}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$PBr _{3}+3H _{2}O\ \to \ H _{3}PO _{4}+HBr$
HBr is covalent $H _{3}PO _{4}$ is ionic. Solution conducts electricity due to ions.
So aqueous solution of $PBr _{3}$ conducts electricity due to presence of $H _{3}PO _{4}$.

Multiple choice chemistry p- block elements-ii compounds of phosphorus - pcl3 phosphorus halides compounds of phosphorus compounds of phosphorus- pcl5

$\mathrm{B}$ottle of $\mathrm{P}\mathrm{C}l _{3}$ is kept stoppered because it :

  1. explodes

  2. gets oxidized

  3. is volatalised

  4. reacts with moisture
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Solution:-
$PCl _3+3H _2O\rightarrow H _3\ PO _3+3HCl$


$PCl _3$ reacts rapidly and exothermically with water to form phosphorus acid ,$H _3PO _3$ and $HCl$.

Option D is correct.

Multiple choice chemistry p- block elements-ii compounds of phosphorus - pcl3 phosphorus halides compounds of phosphorus compounds of phosphorus- pcl5

The products of the hydrolysis of $\mathrm{P}\mathrm{Cl} _{3}$ are :

  1. $\mathrm{H}\mathrm{Cl},\ \mathrm{H} _{3}\mathrm{P}\mathrm{O} _{4}$
  2. $\mathrm{H}\mathrm{Cl},\ \mathrm{H} _{3}\mathrm{P}\mathrm{O} _{3}$
  3. $\mathrm{Cl} _{2},\ \mathrm{H} _{3}\mathrm{P}\mathrm{O} _{3}$
  4. $\mathrm{H}\mathrm{Cl},\ \mathrm{P}\mathrm{O}\mathrm{Cl} _{3},\ \mathrm{H} _{3}\mathrm{P}\mathrm{O} _{4}$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 Hydrolysis of $PCl _3$ gives:

$2PCl _3+6H _2O\rightarrow 2H _3PO _3+6H+$

$PCl _3+3H _2O\rightarrow H _3PO _3+3H+$

Option B is correct.

Multiple choice chemistry p- block elements-ii compounds of phosphorus - pcl3 phosphorus halides compounds of phosphorus compounds of phosphorus- pcl5

The products formed by the complete hydrolysis of $P{Cl} _{3}$ are:

  1. ${H} _{3}{PO} _{3}$ and $HCl$
  2. $PO{Cl} _{3}$ and $HCl$
  3. ${H} _{3}{PO} _{4}$ and $HCl$
  4. ${H} _{4}{P} _{2}{O} _{7}$ and $HCl$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The products formed by the complete hydrolysis of $PCl _3$ are as follow:
$PC{ l } _{ 3 }+3{ H } _{ 2 }O\rightarrow { H } _{ 3 }P{ O } _{ 3 }+3HCl$

${ H } _{ 3 }P{ O } _{ 3 }$ and $HCl$ are the products formed.
Multiple choice chemistry p- block elements-ii compounds of phosphorus - pcl3 phosphorus halides compounds of phosphorus compounds of phosphorus- pcl5

On hydrolysis, $PCI _3$ gives :

  1. $H _3PO _3$
  2. $H _3PO _4$
  3. $POCI _3$
  4. $HPO _3$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
$PCl _{3}$ on hydrolysis gives $HCl$ and $ H _{3}PO _{3}$

$PCl _{3}+ 3H _{2}O\rightarrow H _{3}PO _{3}+3HCl$

Phosphorus trichloride reacts violently with water forming phosphorous acid.

Option (A) is correct .

Multiple choice chemistry p- block elements-ii compounds of phosphorus - pcl3 phosphorus halides compounds of phosphorus compounds of phosphorus- pcl5

Choose the correct statement.

  1. White or yellow phosphorus is stored under water

  2. Ignition temperature of red phosphorus is low

  3. Black phosphorus is non crystalline in nature

  4. Phosphorus does not form hydrides
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Due to low ignition temperature of white phosphorus, it undergoes oxidation in presence of air which slowly raises its temperature and after a few moments it catches fire spontaneously. Due to this reason, it is stored under water. Ignition temperature ofred phosphorus is high Black phosphorus is crystalline in nature. Phosphorus forms a number of hydrides