Tag: p- block elements-ii

Questions Related to p- block elements-ii

What is the hybridization state of cation part of solid $PCl _5$?

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

  1. $sp^3d^2$

  2. $sp^2$

  3. $sp^3$

  4. $sp^3d$

Show answer
Correct Option: C
Explanation:

In solid state, $PCl _5$ prefers to exist as oppositely charged ions like $[PCl _4]^+ PCl _6^-$ as ionic bonding enhances the crystalline nature. Also, $[PCl _4]^+  = sp^3$ is tetrahedral while $[PCl _6^-]$ is octahedral. These structures fit well into each other providing extra stability to the soild structure.

Thus, solid $PCl _5$ exist as $[PCl _4]^+[PCl _6]^-$
The cationic part of $PCl _5$ is$[PCl _4]^+$.
In $PCl _4^+$, Phosphorous forms $4\ \sigma-bonds$. 
Hence, the hybridization is $sp^3$.

In presence of small amount of water, $PCl _5$ hydrolyzes to form :

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

  1. $PCl _3$

  2. POCl

  3. $POCl _3$

  4. $H _3PO _3$

Show answer
Correct Option: C
Explanation:

In limited amount of water,
$PCl _5 (s)+H _2O (l)\rightarrow POCl _3(l) + 2HCl(aq)$
In large amount of water,
$PCl _5(s) +4H _2O(l)\rightarrow H _3PO _4+ 5HCl$

Hence, the correct option is (C).

Which of the following statements is/are correct?

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

  1. Solid $PCl _5$ exists as tetrahedral $PCl^{+} _{4}$ and octahedral $PCl^{-} _{6}$ ions.

  2. Solid $PBr _5$ exists as $PBr^{+} _{4}Br^{-}$.

  3. Solid $N _2O _5$ exists as $NO^{-} _3$ and $NO^{+} _{2}$.

  4. Oxides of phosphorus $P _2O _3$ and $P _2O _5$ exist as monomers.

Show answer
Correct Option: A,B,C
Explanation:

Solid $PCl _5$ exists as tetrahedral $PCl^{+} _{4}$ and octahedral  $PCl^{-} _{6}$ ions.
$2PCl _5 \rightleftharpoons [PCl _4]^+ (tetrahedral) + [PCl _6]^-(octahedral)$
Solid $PBr _5$ exists as $PBr^{+} _{4}Br^{-}$.
$PBr _5 \rightleftharpoons [PBr _4]^+(tetrahedral) Br^-$
Solid $N _2O _5$ exists as $NO^{-} _3$ and $NO^{+} _{2}$.
$N _2O _5 \rightleftharpoons NO^{-} _3 + NO^{+} _{2}$
Oxides of phosphorus $P _2O _3$ and $P _2O _5$ exist as dimers $P _4O _6$ and $P _4O _{10}$. 

All these are facts. Thus, the options A, B and C are correct and option D is incorrect.

$PCl _5$ exists as solid in the form of $[PCl _4]^{+} [PCl _6]^{-}$, and it is a non conductor of electricity.

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

  1. True 

  2. False

  3. Ambiguous

  4. None of the above

Show answer
Correct Option: A
Explanation:

In solid state, position of ions are fixed, and hence, cannot conduct electricity.

In the following reactions :
$(i) P{Cl} _{5}+{SO} _{2}\rightarrow A+B$
$(ii) A+MeCOOH\rightarrow C+{SO} _{2}+HCl$
$(iii) 2C+{Me} _{2}Cd\rightarrow 2D+CD{Cl} _{2}$ The compound (C) is:

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

  1. $Me-CH -Cl _2$

  2. $Me-CH _2 -Cl$

  3. $Me-\underset { \parallel \ O }{ C } -Cl$

  4. $Me-C -Cl _3$

Show answer
Correct Option: C
Explanation:

$(i) P{Cl} _{5}+{SO} _{2}\rightarrow SO{Cl} _{2} (A)+PO{cl} _{3} (B)$

(ii) $SO{Cl} _{2}+MeCOOH\rightarrow Me-\underset { \parallel \ O }{ C } -Cl (C)+{SO} _{2}+HCl\$

Action of $PCl _5$ on $SO _2$ chiefly yields :

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

  1. $POCl _3$

  2. $P _4S _3$

  3. $SO _2Cl _2$

  4. $SO _3$

Show answer
Correct Option: A
Explanation:

$PCl _{5}+SO _{2}\rightarrow POCl _{3}+SOCl _{2}$

Unsymmetrical $PCl _5(s)$ splits into $PCl _4^+$ and  $PCl _6^-$.

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

  1. True

  2. False

  3. Ambiguous

  4. None of these

Show answer
Correct Option: A
Explanation:

The cation $PCl^+ _4$ and the anion $PCl _6^-$ are tetrahedral and octahedral which are more stable then $PCl _5$ due to symmetry.

$PCl _5$ in soild state dissociates into $PCl^+ _4$ and $PCl^- _6$.

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

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

The given statement is True.
 
$\displaystyle PCl _5$ molecule has trigonal bipyramidal geometry which is unstable as axial P-Cl bonds are slightly larger than equatorial P-Cl bonds. Also some bond angles are of 90 deg and others are of 120 deg. Due to this, trigonal bipyramidal geometry is not regular and not stable. Hence, in solid state, $\displaystyle PCl _5$ molecule dissociates into tetrahedral $\displaystyle [PCl _4]^+$ and octahedral $\displaystyle [PCl _6]^-$
$\displaystyle 2PCl _5 \rightleftharpoons [PCl _4]^+ +[PCl _6]^- $

The compound molecular in nature in gas phase but ionic in solid state is :

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

  1. $ PCl _5 $

  2. $ CCl _4 $

  3. $ PCl _3 $

  4. $ POCl _3 $

  5. None of the above

Show answer
Correct Option: A
Explanation:

In gaseous and molten state $PCl _5$ is neutral molecule with trigonal bipyramidal symmetry.

In solid state $PCl _5$ is ionic which forms $PCl _4^{+}$, $PCl _6^{-}$. The cation and anion $PCl _4^{+}$, $PCl _6^{-}$ are tetrahedral and octahedral respectively.

Hence option A is correct.

When three parts of conc. HCl and one part of conc. $HNO _{3}$ is mixed, a compound 'X' is formed. The correct option related to 'X' is:

chemistry p- block elements-ii hydrogen chloride chlorine - 17 group p-block elements

  1. 'X' is known as aqua-regia

  2. 'X' is used for dissolving gold

  3. 'X' is used for decomposition of salts of weaker acids

  4. both (a) and (b)

Show answer
Correct Option: D
Explanation:

Aqua regia is also called as royal water is a mixture of nitric acid and hydrochloric acid in the  molar ratio of 1:3. Aqua regia is a yellow-orange fuming liquid.Aqua regia is used for the decomposition of weak acids.

Hene option D is correct.