P Block Elements - Inorganic Chemistry - Chemistry Previous Year Questions

Observe the following reactions (unbalanced)

$ \begin{array}{r} \mathrm{P}_{2} \mathrm{O}_{3}+\mathrm{H}_{2} \mathrm{O} \longrightarrow X \\ \mathrm{P}_{4} \mathrm{O}_{10}+\mathrm{H}_{2} \mathrm{O} \longrightarrow Y \end{array} $

The number of $\mathrm{P}=\mathrm{O}$ bonds present in $X, Y$ are respectively

What are $X$ and $Y$ respectively in the following reactions ?

$ X \stackrel{\mathrm{CO}}{\longleftarrow} \mathrm{~B}_{2} \mathrm{H}_{6} \xrightarrow[\left(\mathrm{C}_{2} \mathrm{H}_{5}\right)_{2} \mathrm{O}]{\mathrm{NaH}} Y $

Which of the following statements are correct?

(i) $\mathrm{CCl}_{4}$ undergoes hydrolysis easily

(ii) Diamond has directional covalent bonds

(iii) Fullerene is thermodynamically most stable allotrope of carbon

(iv) Glass is a man-made silicate

The correct answer is

Observe the following species.

(i) $\mathrm{NH}_3$

(ii) $\mathrm{AlCl}_3$

(iii) $\mathrm{SnCl}_4$

(iv) $\mathrm{CO}_2$

(v) $\mathrm{Ag}^{+}$

(vi) $ \mathrm{HSO}_{4}^{-} $

How many of the above species act as Lewis acids?

Which among the following oxoacids of phosphorous will have $\mathrm{P}-\mathrm{O}-\mathrm{P}$ bonds?

I. $\mathrm{H}_{4} \mathrm{P}_{2} \mathrm{O}_{5}$

II. $\mathrm{H}_{4} \mathrm{P}_{2} \mathrm{O}_{6}$

III. $\mathrm{H}_{4} \mathrm{P}_{2} \mathrm{O}_{7}$

IV. $\left(\mathrm{HPO}_{3}\right)_{3}$

Consider the following reactions (not balanced).

$$\begin{array}{r} \mathrm{BF}_3+\mathrm{NaH} \xrightarrow{450 \mathrm{~K}} X+\mathrm{NaF} \\ X+\mathrm{H}_2 \mathrm{O} \longrightarrow Y+\mathrm{H}_2 \uparrow \end{array}$$

The correct statements about $X$ and $Y$ are

I. $X$ is an electron deficient molecule.

II. in $X, B-B$ bond is present.

III. $Y$ is a weak tribasic acid.

IV. $Y$ acts as a Lewis acid.

Consider the following reactions.

$$X+\mathrm{O}_2 \rightarrow \mathrm{Cu}_2 \mathrm{O}+\mathrm{SO}_2, \mathrm{Cu}_2 \mathrm{O}+X \rightarrow \mathrm{Cu}+Y \uparrow$$

The shape of the molecule $Y$ is

Zinc on reaction with concentrated nitric acid gives an oxide of nitrogen $(A)$. Zinc with dilute nitric acid gives another oxide of nitrogen $(B)$. Oxidation numbers of nitrogen in $(A)$ and $(B)$ are respectively

An oxoacid of phosphorus ' $X$ ' reduces silver nitrate solution to metallic silver and gets oxidised to another compound $Y . X$ and $Y$ respectively are

The correct statements about the compounds of boron are

I. In borax bead test, the colour of cobalt metaborate is blue.

II. Diborane is prepared by the oxidation of sodium borohydride with iodine.

III. In diborane oxidation state of hydrogen is +1 .

IV. Boric acid is a tribasic acid.

Identify the reaction related to Deacon's process

Phosphorus on reaction with sulphuryl chloride gives a compound $X$, which on complete hydrolysis gives $Y$. $X$ and $Y$ are respectively.